65 câu hỏi
Choose the answer among A,B,C,D whose underlined part is pronunciated differently from the others.
father
healthy
other
another
Choose the answer among A,B,C,D whose underlined part is pronunciated differently from the others.
washed
matched
intended
walked
Choose the answer among A,B,C,D whose stress position is different from the others
appear
decide
require
cancel
Choose the answer among A,B,C,D whose stress position is different from the others
eradication
resolution
contradiction
similarity
Choose the answer among A,B,C,D whose stress position is different from the others
reformulate
scientific
considerable
exclude
Choose the answer among A,B,C,D to complete each of the sentences below:
The book___________ you are reading is really useful for all the exams
which
who
what
it
Choose the answer among A,B,C,D to complete each of the sentences below:
When I passed their house, all the lights had been turned off. They_____________ to bed already.
must go
should have gone
must have gone
need have gone
Choose the answer among A,B,C,D to complete each of the sentences below:
__________ really worn out from hard work, she managed to amuse us with a funny story.
Despite
Because of
Because
Although
Choose the answer among A,B,C,D to complete each of the sentences below:
By this time next year, my new house___________, and we can move into it.
will finish
will have been finished
will have finished
will be finished
Choose the answer among A,B,C,D to complete each of the sentences below:
It is no good____________ to him about the problem. He’s as deaf as a pole.
complain
to complain
complaining
complaint
Choose the answer among A,B,C,D to complete each of the sentences below:
I am wondering what____________if our ecosystem were completely destroyed?
will happen
would have happened
happened
would happen
Choose the answer among A,B,C,D to complete each of the sentences below:
Jane: “Did you step on her foot by accident or________ purpose?” Mary: “Delibrately”
on
in
by
through
Choose the answer among A,B,C,D to complete each of the sentences below:
My sister has just bought a___________at that shop, which is situated at the corner of Tran Phu Street.
pullover beautiful pink woolen
pink beautiful woolen pullover
beautiful pink woolen pullover
woolen beautiful pink pullover
Choose the answer among A,B,C,D to complete each of the sentences below:
ould you please give me a lift to work tomorrow? My motorbike is____________today.
out of date
out of work
out of mind
out of order
Choose the answer among A,B,C,D to complete each of the sentences below:
We put his rude manner___________ignorance of the local customs .
down to
up with
up to
off at
Choose the answer among A,B,C,D to complete each of the sentences below:
He has devoured to learn English the past months ___________getting a chance to study abroad.
with a view of
with a view to
in regard of
on account of.
Choose the answer among A,B,C,D to complete each of the sentences below:
The more distance a star happens to be, ______________ to us.
it seems dimmer
the dimmest it seems
the dimmer it seems
it seems dimmest
Choose the answer among A,B,C,D to complete each of the sentences below:
The job was done____________, and we were extremely displeased.
incompetence
incompetent
competently
incompetently
Choose the answer among A,B,C,D to complete each of the sentences below:
His change of job has___________ him with a new challenge in life.
presented
introduced
initiated
led
Choose the answer among A,B,C,D to complete each of the sentences below:
Not until my mother got home________________that she had left the purse at the office.
that she realized
she realized
did she realize
did she realized
Choose the answer among A,B,C,D to complete each of the sentences below:
In order to grow vegetables productively, gardeners must know______________.
that the requirements for each vegetable
what the requirements for each vegetable are
what are each vegetables’ requirements
that is required by each vegetable
Choose the answer among A,B,C,D to complete each of the sentences below:
David: “ The final exams are coming. I seem to be too nervous!” Linda: “___________________. It will be not so hard as you’ve expected.
Be careful
Good Luck
Congratulations
Take it easy
Choose the answer among A,B,C,D to complete each of the sentences below:
Son: “ Why don”t we buy a new car, Dad? This one is too old to go out with my friends.” Dad: “ ______________. We don’t have much money.”
It is out of the question now
I have to think it over
You are right
That’s a great idea.
Choose the answer among A,B,C,D to complete each of the sentences below:
Kenny: “ Your hairstyle is terrific!” Linda: “____________”
It’s a nice compliment. Thank you.
Not at all
The same to you
Really? Congratulaions!
Choose the best answer among A,B,C,D whose meaning is CLOSEST to the underlined part in each sentence below:
The population of the United States is roughly 240 million.
unfortunately
ideally
approximately
usuallya
Choose the best answer among A,B,C,D whose meaning is CLOSEST to the underlined part in each sentence below:
A legal combination of Delta Airlines and Air France was approved at a joint board of directors meeting.
reconciliation
strike
memorandum
merger
Choose the best answer among A,B,C,D whose meaning is CLOSEST to the underlined part in each sentence below:
According to federal regulations, it is required that all canned and packaged food have a list of the items used in the recipe printed in the label.
ailments
blandishments
remnants
ingredients
Choose the best answer among A,B,C,D whose meaning is OPPOSITE to the underlined part in each sentence below:
We didn’t plan to meet each other. We just met accidentally.
intentionally
simultanously
hurriedly
coincidently
Choose the best answer among A,B,C,D whose meaning is OPPOSITE to the underlined part in each sentence below:
The smell of the fish put me off the meal.
interested me
made me unable to eat the meal
made me want to eat the meal a lot
made me feel hungry
Choose the best answer among A,B,C,D whose meaning is OPPOSITE to the underlined part in each sentence below:
The smell of the fish put me off the meal.
interested me
made me unable to eat the meal
made me want to eat the meal a lot
made me feel hungry
Choose the answer among A,B,C,D whose underlined part needs correcting to make sentences below complete:
Jim was upset (A) last night because (B) he had to do (C) too many homeworks. (D)
upset
because
had to do
many homeworks
Choose the answer among A,B,C,D whose underlined part needs correcting to make sentences below complete:
The professor told him (A) to write a short but it must becomprehensive (B) paper about (C) the experiment (D)
him
it must becomprehensive
about
experiment
Choose the answer among A,B,C,D whose underlined part needs correcting to make sentences below complete:
This table is not sturdy enough (A) to support (B) a television, and that one (C) probably isn't neither. (D)
not sturdy enough
to support
that one
neither
Choose the answer among A,B,C,D whose underlined part needs correcting to make sentences below complete:
Lectures for (A) the week of March 22-26 will include (B) the following:(C) The Causes of the Civil War, The Economy of the South, Battle Strategies, and Assassinating Lincoln. (D)
for
will include
following
Assassinating Lincoln
Choose the answer among A,B,C,D whose underlined part needs correcting to make sentences below complete:
In 1975, according to (A) the National Center for Health Statistics, the average life expectancy for people born (B) during (C) that year is (D) 72.4 years.
according to
born
during
is
Read the passage and choose the best answer among A,B,C,D for each gap to complete it. Fill in the appropriate word in question 35
Most people feel that when they dream, they are (35)________ off to another world. On the (36)________, dreams are often connected to our daily lives. When our whole (37)_________ is filled with something, when we are either very upset (38)________ when we are in good spirit, a dream will represent this reality in symbols. It is often (39)_______ that we benefit from dreams because they help the spirit to heal itself when things (40)__________ wrong. Dreams are therefore a kind of escape, almost a holiday from (41)__________ life, with its fears and responsibilities. It is, however, a strange kind of holiday because whether we have a wonderful time or whether it turns (42)_________ to be a nightmare, we quickly forget it. Most dreams disappear forever, (43)_________ you are one of those people disciplined enough to write them down as soon as you (44)_________.
taken
guided
brought
carried
Read the passage and choose the best answer among A,B,C,D for each gap to complete it. Fill in the appropriate word in question 36
Most people feel that when they dream, they are (35)________ off to another world. On the (36)________, dreams are often connected to our daily lives. When our whole (37)_________ is filled with something, when we are either very upset (38)________ when we are in good spirit, a dream will represent this reality in symbols. It is often (39)_______ that we benefit from dreams because they help the spirit to heal itself when things (40)__________ wrong. Dreams are therefore a kind of escape, almost a holiday from (41)__________ life, with its fears and responsibilities. It is, however, a strange kind of holiday because whether we have a wonderful time or whether it turns (42)_________ to be a nightmare, we quickly forget it. Most dreams disappear forever, (43)_________ you are one of those people disciplined enough to write them down as soon as you (44)_________.
contrast
contrary
other side
opposite
Read the passage and choose the best answer among A,B,C,D for each gap to complete it. Fill in the appropriate word in question 37
Most people feel that when they dream, they are (35)________ off to another world. On the (36)________, dreams are often connected to our daily lives. When our whole (37)_________ is filled with something, when we are either very upset (38)________ when we are in good spirit, a dream will represent this reality in symbols. It is often (39)_______ that we benefit from dreams because they help the spirit to heal itself when things (40)__________ wrong. Dreams are therefore a kind of escape, almost a holiday from (41)__________ life, with its fears and responsibilities. It is, however, a strange kind of holiday because whether we have a wonderful time or whether it turns (42)_________ to be a nightmare, we quickly forget it. Most dreams disappear forever, (43)_________ you are one of those people disciplined enough to write them down as soon as you (44)_________.
spirit
mind
brain
soul
Read the passage and choose the best answer among A,B,C,D for each gap to complete it. Fill in the appropriate word in question 38
Most people feel that when they dream, they are (35)________ off to another world. On the (36)________, dreams are often connected to our daily lives. When our whole (37)_________ is filled with something, when we are either very upset (38)________ when we are in good spirit, a dream will represent this reality in symbols. It is often (39)_______ that we benefit from dreams because they help the spirit to heal itself when things (40)__________ wrong. Dreams are therefore a kind of escape, almost a holiday from (41)__________ life, with its fears and responsibilities. It is, however, a strange kind of holiday because whether we have a wonderful time or whether it turns (42)_________ to be a nightmare, we quickly forget it. Most dreams disappear forever, (43)_________ you are one of those people disciplined enough to write them down as soon as you (44)_________.
unless
but also
or else
or
Read the passage and choose the best answer among A,B,C,D for each gap to complete it. Fill in the appropriate word in question 39
Most people feel that when they dream, they are (35)________ off to another world. On the (36)________, dreams are often connected to our daily lives. When our whole (37)_________ is filled with something, when we are either very upset (38)________ when we are in good spirit, a dream will represent this reality in symbols. It is often (39)_______ that we benefit from dreams because they help the spirit to heal itself when things (40)__________ wrong. Dreams are therefore a kind of escape, almost a holiday from (41)__________ life, with its fears and responsibilities. It is, however, a strange kind of holiday because whether we have a wonderful time or whether it turns (42)_________ to be a nightmare, we quickly forget it. Most dreams disappear forever, (43)_________ you are one of those people disciplined enough to write them down as soon as you (44)_________.
said
spoken
declared
started
Read the passage and choose the best answer among A,B,C,D for each gap to complete it. Fill in the appropriate word in question 40
Most people feel that when they dream, they are (35)________ off to another world. On the (36)________, dreams are often connected to our daily lives. When our whole (37)_________ is filled with something, when we are either very upset (38)________ when we are in good spirit, a dream will represent this reality in symbols. It is often (39)_______ that we benefit from dreams because they help the spirit to heal itself when things (40)__________ wrong. Dreams are therefore a kind of escape, almost a holiday from (41)__________ life, with its fears and responsibilities. It is, however, a strange kind of holiday because whether we have a wonderful time or whether it turns (42)_________ to be a nightmare, we quickly forget it. Most dreams disappear forever, (43)_________ you are one of those people disciplined enough to write them down as soon as you (44)_________.
become
go
turn
get
Read the passage and choose the best answer among A,B,C,D for each gap to complete it. Fill in the appropriate word in question 41
Most people feel that when they dream, they are (35)________ off to another world. On the (36)________, dreams are often connected to our daily lives. When our whole (37)_________ is filled with something, when we are either very upset (38)________ when we are in good spirit, a dream will represent this reality in symbols. It is often (39)_______ that we benefit from dreams because they help the spirit to heal itself when things (40)__________ wrong. Dreams are therefore a kind of escape, almost a holiday from (41)__________ life, with its fears and responsibilities. It is, however, a strange kind of holiday because whether we have a wonderful time or whether it turns (42)_________ to be a nightmare, we quickly forget it. Most dreams disappear forever, (43)_________ you are one of those people disciplined enough to write them down as soon as you (44)_________.
real
factual
genuine
actual
Read the passage and choose the best answer among A,B,C,D for each gap to complete it. Fill in the appropriate word in question 42
Most people feel that when they dream, they are (35)________ off to another world. On the (36)________, dreams are often connected to our daily lives. When our whole (37)_________ is filled with something, when we are either very upset (38)________ when we are in good spirit, a dream will represent this reality in symbols. It is often (39)_______ that we benefit from dreams because they help the spirit to heal itself when things (40)__________ wrong. Dreams are therefore a kind of escape, almost a holiday from (41)__________ life, with its fears and responsibilities. It is, however, a strange kind of holiday because whether we have a wonderful time or whether it turns (42)_________ to be a nightmare, we quickly forget it. Most dreams disappear forever, (43)_________ you are one of those people disciplined enough to write them down as soon as you (44)_________.
off
up
out
down
Read the passage and choose the best answer among A,B,C,D for each gap to complete it. Fill in the appropriate word in question 43
Most people feel that when they dream, they are (35)________ off to another world. On the (36)________, dreams are often connected to our daily lives. When our whole (37)_________ is filled with something, when we are either very upset (38)________ when we are in good spirit, a dream will represent this reality in symbols. It is often (39)_______ that we benefit from dreams because they help the spirit to heal itself when things (40)__________ wrong. Dreams are therefore a kind of escape, almost a holiday from (41)__________ life, with its fears and responsibilities. It is, however, a strange kind of holiday because whether we have a wonderful time or whether it turns (42)_________ to be a nightmare, we quickly forget it. Most dreams disappear forever, (43)_________ you are one of those people disciplined enough to write them down as soon as you (44)_________.
except that
therefore
thus
unless
Read the passage and choose the best answer among A,B,C,D for each gap to complete it. Fill in the appropriate word in question 44
Most people feel that when they dream, they are (35)________ off to another world. On the (36)________, dreams are often connected to our daily lives. When our whole (37)_________ is filled with something, when we are either very upset (38)________ when we are in good spirit, a dream will represent this reality in symbols. It is often (39)_______ that we benefit from dreams because they help the spirit to heal itself when things (40)__________ wrong. Dreams are therefore a kind of escape, almost a holiday from (41)__________ life, with its fears and responsibilities. It is, however, a strange kind of holiday because whether we have a wonderful time or whether it turns (42)_________ to be a nightmare, we quickly forget it. Most dreams disappear forever, (43)_________ you are one of those people disciplined enough to write them down as soon as you (44)_________.
wake up
arise
awake
rise up
Read the passage and choose the best answer for each question below.
It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species’ death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be able to adapt. Food Resources may be affected by environmental changes, which will then cause problems. For a species requiring these resources. Other species may become better adapted to an Environment, resulting in competition and, ultimately, in the death of a species.
The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time – a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life.
Perhaps the largest mass extinction was the one that occurred 225 million years ago, When approximately 95 percent of all species died, Mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, affection even organisms not living in the oceans. Such a change would probably lead to a mass extinction.
One interesting, and controversial, finding is that extinctions during the past 250 Million years have tended to be more intense every 26 million years. This periodic extinction might be due to intersection of the Earth’s orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated tat extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species’ survival may have nothing to do with its ability or inability to adapt. If so, some of evolutionary history may reflect a sequence of essentially random events.
The word “it” in line 2 refers to
environment
species
extinction
99 percent
Read the passage and choose the best answer for each question below.
It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species’ death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be able to adapt. Food Resources may be affected by environmental changes, which will then cause problems. For a species requiring these resources. Other species may become better adapted to an Environment, resulting in competition and, ultimately, in the death of a species.
The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time – a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life.
Perhaps the largest mass extinction was the one that occurred 225 million years ago, When approximately 95 percent of all species died, Mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, affection even organisms not living in the oceans. Such a change would probably lead to a mass extinction.
One interesting, and controversial, finding is that extinctions during the past 250 Million years have tended to be more intense every 26 million years. This periodic extinction might be due to intersection of the Earth’s orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated tat extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species’ survival may have nothing to do with its ability or inability to adapt. If so, some of evolutionary history may reflect a sequence of essentially random events.
The word “ultimately” in line 7 is closest in meaning to
exceptionally
dramatically
eventually
unfortunately
Read the passage and choose the best answer for each question below.
It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species’ death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be able to adapt. Food Resources may be affected by environmental changes, which will then cause problems. For a species requiring these resources. Other species may become better adapted to an Environment, resulting in competition and, ultimately, in the death of a species.
The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time – a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life.
Perhaps the largest mass extinction was the one that occurred 225 million years ago, When approximately 95 percent of all species died, Mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, affection even organisms not living in the oceans. Such a change would probably lead to a mass extinction.
One interesting, and controversial, finding is that extinctions during the past 250 Million years have tended to be more intense every 26 million years. This periodic extinction might be due to intersection of the Earth’s orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated tat extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species’ survival may have nothing to do with its ability or inability to adapt. If so, some of evolutionary history may reflect a sequence of essentially random events.
What does the author say in paragraph 1 regarding most species in Earth’s history
They have remained basically unchanged from their original forms.
They have been able to adapt to ecological changes.
They have caused rapid change in the environment.
They are no longer in existence.
Read the passage and choose the best answer for each question below.
It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species’ death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be able to adapt. Food Resources may be affected by environmental changes, which will then cause problems. For a species requiring these resources. Other species may become better adapted to an Environment, resulting in competition and, ultimately, in the death of a species.
The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time – a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life.
Perhaps the largest mass extinction was the one that occurred 225 million years ago, When approximately 95 percent of all species died, Mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, affection even organisms not living in the oceans. Such a change would probably lead to a mass extinction.
One interesting, and controversial, finding is that extinctions during the past 250 Million years have tended to be more intense every 26 million years. This periodic extinction might be due to intersection of the Earth’s orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated tat extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species’ survival may have nothing to do with its ability or inability to adapt. If so, some of evolutionary history may reflect a sequence of essentially random events.
Which of the following is NOT mentioned in paragraph 1 as resulting from rapid ecological change?
Temperature changes
Availability of food resources
Introduction of new species
Competition among species
Read the passage and choose the best answer for each question below.
It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species’ death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be able to adapt. Food Resources may be affected by environmental changes, which will then cause problems. For a species requiring these resources. Other species may become better adapted to an Environment, resulting in competition and, ultimately, in the death of a species.
The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time – a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life.
Perhaps the largest mass extinction was the one that occurred 225 million years ago, When approximately 95 percent of all species died, Mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, affection even organisms not living in the oceans. Such a change would probably lead to a mass extinction.
One interesting, and controversial, finding is that extinctions during the past 250 Million years have tended to be more intense every 26 million years. This periodic extinction might be due to intersection of the Earth’s orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated tat extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species’ survival may have nothing to do with its ability or inability to adapt. If so, some of evolutionary history may reflect a sequence of essentially random events.
Why is “ plankton” mentioned in line 15?
To demonstrate the interdependence of different species
To emphasize the importance of food resources in preventing mass extinction.
To illustrate a comparison between organisms that live on the land and those that live in the ocean
To point out that certain species could never become extinct.
Read the passage and choose the best answer for each question below.
It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species’ death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be able to adapt. Food Resources may be affected by environmental changes, which will then cause problems. For a species requiring these resources. Other species may become better adapted to an Environment, resulting in competition and, ultimately, in the death of a species.
The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time – a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life.
Perhaps the largest mass extinction was the one that occurred 225 million years ago, When approximately 95 percent of all species died, Mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, affection even organisms not living in the oceans. Such a change would probably lead to a mass extinction.
One interesting, and controversial, finding is that extinctions during the past 250 Million years have tended to be more intense every 26 million years. This periodic extinction might be due to intersection of the Earth’s orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated tat extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species’ survival may have nothing to do with its ability or inability to adapt. If so, some of evolutionary history may reflect a sequence of essentially random events.
According to paragraph 2, evidence from fossils suggests that
extinction of species has occurred from time to time throughout Earth’s history.
Extinctions on Earth have generally been massive
there has been only one mass extinction in Earth’s history.
dinosaurs became extinct much earlier than scientists originally believed.
Read the passage and choose the best answer for each question below.
It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species’ death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be able to adapt. Food Resources may be affected by environmental changes, which will then cause problems. For a species requiring these resources. Other species may become better adapted to an Environment, resulting in competition and, ultimately, in the death of a species.
The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time – a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life.
Perhaps the largest mass extinction was the one that occurred 225 million years ago, When approximately 95 percent of all species died, Mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, affection even organisms not living in the oceans. Such a change would probably lead to a mass extinction.
One interesting, and controversial, finding is that extinctions during the past 250 Million years have tended to be more intense every 26 million years. This periodic extinction might be due to intersection of the Earth’s orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated tat extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species’ survival may have nothing to do with its ability or inability to adapt. If so, some of evolutionary history may reflect a sequence of essentially random events.
The word “finding” in line 18 is closest in meaning to
published information
research method
ongoing experiment
scientific discovery
Read the passage and choose the best answer for each question below.
It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species’ death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be able to adapt. Food Resources may be affected by environmental changes, which will then cause problems. For a species requiring these resources. Other species may become better adapted to an Environment, resulting in competition and, ultimately, in the death of a species.
The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time – a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life.
Perhaps the largest mass extinction was the one that occurred 225 million years ago, When approximately 95 percent of all species died, Mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, affection even organisms not living in the oceans. Such a change would probably lead to a mass extinction.
One interesting, and controversial, finding is that extinctions during the past 250 Million years have tended to be more intense every 26 million years. This periodic extinction might be due to intersection of the Earth’s orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated tat extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species’ survival may have nothing to do with its ability or inability to adapt. If so, some of evolutionary history may reflect a sequence of essentially random events.
The word “demise” in line 11 is closest in meaning to
change
recovery
help
death
Read the passage and choose the best answer for each question below.
It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species’ death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be able to adapt. Food Resources may be affected by environmental changes, which will then cause problems. For a species requiring these resources. Other species may become better adapted to an Environment, resulting in competition and, ultimately, in the death of a species.
The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time – a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life.
Perhaps the largest mass extinction was the one that occurred 225 million years ago, When approximately 95 percent of all species died, Mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, affection even organisms not living in the oceans. Such a change would probably lead to a mass extinction.
One interesting, and controversial, finding is that extinctions during the past 250 Million years have tended to be more intense every 26 million years. This periodic extinction might be due to intersection of the Earth’s orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated tat extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species’ survival may have nothing to do with its ability or inability to adapt. If so, some of evolutionary history may reflect a sequence of essentially random events.
In paragraph 3, the author makes which of the following statements about a species’ survival?
It reflects the interrelationship of may species.
It may depend on chance events.
It does not vary greatly from species to species
It is associated with astronomical conditions.
Read the passage and choose the best answer for each question below.
It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species’ death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be able to adapt. Food Resources may be affected by environmental changes, which will then cause problems. For a species requiring these resources. Other species may become better adapted to an Environment, resulting in competition and, ultimately, in the death of a species.
The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time – a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life.
Perhaps the largest mass extinction was the one that occurred 225 million years ago, When approximately 95 percent of all species died, Mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, affection even organisms not living in the oceans. Such a change would probably lead to a mass extinction.
One interesting, and controversial, finding is that extinctions during the past 250 Million years have tended to be more intense every 26 million years. This periodic extinction might be due to intersection of the Earth’s orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated tat extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species’ survival may have nothing to do with its ability or inability to adapt. If so, some of evolutionary history may reflect a sequence of essentially random events.
According to the passage, it is believed that the largest extinction of a species occurred
26 million years ago
65 million years ago
225 million years ago
250 million years ago
Read the passage and choose the best answer for each question below.
By far the most important United States export product in the eighteenth and nineteenth centuries was cotton, favored by the European textile industry over flax or wool because it was easy to process and soft to tile touch. Mechanization of spinning and weaving allowed significant centralization and expansion in the textile industry during
this period, and at the same time the demand for cotton increased dramatically. American producers were able to meet this demand largely because of tile invention of the cotton gin by Eli Whitney in 1793. Cotton could be grown throughout the South, but separating the fiber – or lint – from the seed was a laborious process. Sea island cotton was relatively easy to process by hand, because its fibers were long and seeds were concentrated at the base of the flower, but it demanded a long growing season, available only along the nation's eastern seacoast. Short-staple cotton required a much shorter growing season, but the shortness of the fibers and their mixture with seeds meant that a worker could
hand-process only about one pound per day. Whitney's gin was a hand-powered machine with revolving drums and metal teeth to pull cotton fibers away from seeds. Using the gin, a worker could produce up to 50 pounds of lint a day. The later development of larger gins, powered by horses, water, or steam, multiplied productivity further.
The interaction of improved processing and high demand led to the rapid spread of the cultivation of cotton and to a surge in production. It became the main American export, dwarfing all others. In 1802, cotton composed 14 percent of total American exports by value. Cotton had a 36 percent share by 1810 and over a 50 percent share
in 1830. In 1860, 61 percent of the value of American exports was represented by cotton. In contrast, wheat and wheat flour composed only 6 percent of the value of American exports in that year. Clearly, cotton was king in the trade of the young republic. The growing market for cotton and other American agricultural products led to an unprecedented expansion of agricultural settlement, mostly in the eastern half of the United States---west of the Appalachian Mountains and east of the Mississippi River.
The main point of the passage is that the eighteenth and nineteenth centuries were a time when
the European textile industry increased its demand for American export products
mechanization of spinning and weaving dramatically changed the textile industry
cotton became a profitable crop but was still time-consuming to process
cotton became the most important American export product
Read the passage and choose the best answer for each question below.
By far the most important United States export product in the eighteenth and nineteenth centuries was cotton, favored by the European textile industry over flax or wool because it was easy to process and soft to tile touch. Mechanization of spinning and weaving allowed significant centralization and expansion in the textile industry during
this period, and at the same time the demand for cotton increased dramatically. American producers were able to meet this demand largely because of tile invention of the cotton gin by Eli Whitney in 1793. Cotton could be grown throughout the South, but separating the fiber – or lint – from the seed was a laborious process. Sea island cotton was relatively easy to process by hand, because its fibers were long and seeds were concentrated at the base of the flower, but it demanded a long growing season, available only along the nation's eastern seacoast. Short-staple cotton required a much shorter growing season, but the shortness of the fibers and their mixture with seeds meant that a worker could
hand-process only about one pound per day. Whitney's gin was a hand-powered machine with revolving drums and metal teeth to pull cotton fibers away from seeds. Using the gin, a worker could produce up to 50 pounds of lint a day. The later development of larger gins, powered by horses, water, or steam, multiplied productivity further.
The interaction of improved processing and high demand led to the rapid spread of the cultivation of cotton and to a surge in production. It became the main American export, dwarfing all others. In 1802, cotton composed 14 percent of total American exports by value. Cotton had a 36 percent share by 1810 and over a 50 percent share
in 1830. In 1860, 61 percent of the value of American exports was represented by cotton. In contrast, wheat and wheat flour composed only 6 percent of the value of American exports in that year. Clearly, cotton was king in the trade of the young republic. The growing market for cotton and other American agricultural products led to an unprecedented expansion of agricultural settlement, mostly in the eastern half of the United States---west of the Appalachian Mountains and east of the Mississippi River.
The word "favored" in line 2 is closest in meaning to
preferred
recommended
imported
included
Read the passage and choose the best answer for each question below.
By far the most important United States export product in the eighteenth and nineteenth centuries was cotton, favored by the European textile industry over flax or wool because it was easy to process and soft to tile touch. Mechanization of spinning and weaving allowed significant centralization and expansion in the textile industry during
this period, and at the same time the demand for cotton increased dramatically. American producers were able to meet this demand largely because of tile invention of the cotton gin by Eli Whitney in 1793. Cotton could be grown throughout the South, but separating the fiber – or lint – from the seed was a laborious process. Sea island cotton was relatively easy to process by hand, because its fibers were long and seeds were concentrated at the base of the flower, but it demanded a long growing season, available only along the nation's eastern seacoast. Short-staple cotton required a much shorter growing season, but the shortness of the fibers and their mixture with seeds meant that a worker could
hand-process only about one pound per day. Whitney's gin was a hand-powered machine with revolving drums and metal teeth to pull cotton fibers away from seeds. Using the gin, a worker could produce up to 50 pounds of lint a day. The later development of larger gins, powered by horses, water, or steam, multiplied productivity further.
The interaction of improved processing and high demand led to the rapid spread of the cultivation of cotton and to a surge in production. It became the main American export, dwarfing all others. In 1802, cotton composed 14 percent of total American exports by value. Cotton had a 36 percent share by 1810 and over a 50 percent share
in 1830. In 1860, 61 percent of the value of American exports was represented by cotton. In contrast, wheat and wheat flour composed only 6 percent of the value of American exports in that year. Clearly, cotton was king in the trade of the young republic. The growing market for cotton and other American agricultural products led to an unprecedented expansion of agricultural settlement, mostly in the eastern half of the United States---west of the Appalachian Mountains and east of the Mississippi River.
All of the following are mentioned in the passage as reasons for the increased demand for cotton EXCEPT
cotton's softness
cotton's ease of processing
a shortage of flax and wool
the growth that occurred in the textile industry.
Read the passage and choose the best answer for each question below.
By far the most important United States export product in the eighteenth and nineteenth centuries was cotton, favored by the European textile industry over flax or wool because it was easy to process and soft to tile touch. Mechanization of spinning and weaving allowed significant centralization and expansion in the textile industry during
this period, and at the same time the demand for cotton increased dramatically. American producers were able to meet this demand largely because of tile invention of the cotton gin by Eli Whitney in 1793. Cotton could be grown throughout the South, but separating the fiber – or lint – from the seed was a laborious process. Sea island cotton was relatively easy to process by hand, because its fibers were long and seeds were concentrated at the base of the flower, but it demanded a long growing season, available only along the nation's eastern seacoast. Short-staple cotton required a much shorter growing season, but the shortness of the fibers and their mixture with seeds meant that a worker could
hand-process only about one pound per day. Whitney's gin was a hand-powered machine with revolving drums and metal teeth to pull cotton fibers away from seeds. Using the gin, a worker could produce up to 50 pounds of lint a day. The later development of larger gins, powered by horses, water, or steam, multiplied productivity further.
The interaction of improved processing and high demand led to the rapid spread of the cultivation of cotton and to a surge in production. It became the main American export, dwarfing all others. In 1802, cotton composed 14 percent of total American exports by value. Cotton had a 36 percent share by 1810 and over a 50 percent share
in 1830. In 1860, 61 percent of the value of American exports was represented by cotton. In contrast, wheat and wheat flour composed only 6 percent of the value of American exports in that year. Clearly, cotton was king in the trade of the young republic. The growing market for cotton and other American agricultural products led to an unprecedented expansion of agricultural settlement, mostly in the eastern half of the United States---west of the Appalachian Mountains and east of the Mississippi River.
The word "laborious" in line 6 is closest in meaning to
unfamiliar
primitive
skilled
difficult
Read the passage and choose the best answer for each question below.
By far the most important United States export product in the eighteenth and nineteenth centuries was cotton, favored by the European textile industry over flax or wool because it was easy to process and soft to tile touch. Mechanization of spinning and weaving allowed significant centralization and expansion in the textile industry during
this period, and at the same time the demand for cotton increased dramatically. American producers were able to meet this demand largely because of tile invention of the cotton gin by Eli Whitney in 1793. Cotton could be grown throughout the South, but separating the fiber – or lint – from the seed was a laborious process. Sea island cotton was relatively easy to process by hand, because its fibers were long and seeds were concentrated at the base of the flower, but it demanded a long growing season, available only along the nation's eastern seacoast. Short-staple cotton required a much shorter growing season, but the shortness of the fibers and their mixture with seeds meant that a worker could
hand-process only about one pound per day. Whitney's gin was a hand-powered machine with revolving drums and metal teeth to pull cotton fibers away from seeds. Using the gin, a worker could produce up to 50 pounds of lint a day. The later development of larger gins, powered by horses, water, or steam, multiplied productivity further.
The interaction of improved processing and high demand led to the rapid spread of the cultivation of cotton and to a surge in production. It became the main American export, dwarfing all others. In 1802, cotton composed 14 percent of total American exports by value. Cotton had a 36 percent share by 1810 and over a 50 percent share
in 1830. In 1860, 61 percent of the value of American exports was represented by cotton. In contrast, wheat and wheat flour composed only 6 percent of the value of American exports in that year. Clearly, cotton was king in the trade of the young republic. The growing market for cotton and other American agricultural products led to an unprecedented expansion of agricultural settlement, mostly in the eastern half of the United States---west of the Appalachian Mountains and east of the Mississippi River.
According to the passage, one advantage of sea island cotton was its
abundance of seeds
long fibers
long growing season
adaptability to different climates
Read the passage and choose the best answer for each question below.
By far the most important United States export product in the eighteenth and nineteenth centuries was cotton, favored by the European textile industry over flax or wool because it was easy to process and soft to tile touch. Mechanization of spinning and weaving allowed significant centralization and expansion in the textile industry during
this period, and at the same time the demand for cotton increased dramatically. American producers were able to meet this demand largely because of tile invention of the cotton gin by Eli Whitney in 1793. Cotton could be grown throughout the South, but separating the fiber – or lint – from the seed was a laborious process. Sea island cotton was relatively easy to process by hand, because its fibers were long and seeds were concentrated at the base of the flower, but it demanded a long growing season, available only along the nation's eastern seacoast. Short-staple cotton required a much shorter growing season, but the shortness of the fibers and their mixture with seeds meant that a worker could
hand-process only about one pound per day. Whitney's gin was a hand-powered machine with revolving drums and metal teeth to pull cotton fibers away from seeds. Using the gin, a worker could produce up to 50 pounds of lint a day. The later development of larger gins, powered by horses, water, or steam, multiplied productivity further.
The interaction of improved processing and high demand led to the rapid spread of the cultivation of cotton and to a surge in production. It became the main American export, dwarfing all others. In 1802, cotton composed 14 percent of total American exports by value. Cotton had a 36 percent share by 1810 and over a 50 percent share
in 1830. In 1860, 61 percent of the value of American exports was represented by cotton. In contrast, wheat and wheat flour composed only 6 percent of the value of American exports in that year. Clearly, cotton was king in the trade of the young republic. The growing market for cotton and other American agricultural products led to an unprecedented expansion of agricultural settlement, mostly in the eastern half of the United States---west of the Appalachian Mountains and east of the Mississippi River.
Which of the following can be inferred from the passage about cotton production in the United States after the introduction of Whitney's cotton gin?
More cotton came from sea island cotton plants than before.
More cotton came from short-staple cotton plants than before.
Most cotton produced was sold domestically.
Most cotton produced was exported to England.
Read the passage and choose the best answer for each question below.
By far the most important United States export product in the eighteenth and nineteenth centuries was cotton, favored by the European textile industry over flax or wool because it was easy to process and soft to tile touch. Mechanization of spinning and weaving allowed significant centralization and expansion in the textile industry during
this period, and at the same time the demand for cotton increased dramatically. American producers were able to meet this demand largely because of tile invention of the cotton gin by Eli Whitney in 1793. Cotton could be grown throughout the South, but separating the fiber – or lint – from the seed was a laborious process. Sea island cotton was relatively easy to process by hand, because its fibers were long and seeds were concentrated at the base of the flower, but it demanded a long growing season, available only along the nation's eastern seacoast. Short-staple cotton required a much shorter growing season, but the shortness of the fibers and their mixture with seeds meant that a worker could
hand-process only about one pound per day. Whitney's gin was a hand-powered machine with revolving drums and metal teeth to pull cotton fibers away from seeds. Using the gin, a worker could produce up to 50 pounds of lint a day. The later development of larger gins, powered by horses, water, or steam, multiplied productivity further.
The interaction of improved processing and high demand led to the rapid spread of the cultivation of cotton and to a surge in production. It became the main American export, dwarfing all others. In 1802, cotton composed 14 percent of total American exports by value. Cotton had a 36 percent share by 1810 and over a 50 percent share
in 1830. In 1860, 61 percent of the value of American exports was represented by cotton. In contrast, wheat and wheat flour composed only 6 percent of the value of American exports in that year. Clearly, cotton was king in the trade of the young republic. The growing market for cotton and other American agricultural products led to an unprecedented expansion of agricultural settlement, mostly in the eastern half of the United States---west of the Appalachian Mountains and east of the Mississippi River.
The word "surge" in line 14 is closest in meaning to
sharp increase
sudden stop
important change
excess amount
Read the passage and choose the best answer for each question below.
By far the most important United States export product in the eighteenth and nineteenth centuries was cotton, favored by the European textile industry over flax or wool because it was easy to process and soft to tile touch. Mechanization of spinning and weaving allowed significant centralization and expansion in the textile industry during
this period, and at the same time the demand for cotton increased dramatically. American producers were able to meet this demand largely because of tile invention of the cotton gin by Eli Whitney in 1793. Cotton could be grown throughout the South, but separating the fiber – or lint – from the seed was a laborious process. Sea island cotton was relatively easy to process by hand, because its fibers were long and seeds were concentrated at the base of the flower, but it demanded a long growing season, available only along the nation's eastern seacoast. Short-staple cotton required a much shorter growing season, but the shortness of the fibers and their mixture with seeds meant that a worker could
hand-process only about one pound per day. Whitney's gin was a hand-powered machine with revolving drums and metal teeth to pull cotton fibers away from seeds. Using the gin, a worker could produce up to 50 pounds of lint a day. The later development of larger gins, powered by horses, water, or steam, multiplied productivity further.
The interaction of improved processing and high demand led to the rapid spread of the cultivation of cotton and to a surge in production. It became the main American export, dwarfing all others. In 1802, cotton composed 14 percent of total American exports by value. Cotton had a 36 percent share by 1810 and over a 50 percent share
in 1830. In 1860, 61 percent of the value of American exports was represented by cotton. In contrast, wheat and wheat flour composed only 6 percent of the value of American exports in that year. Clearly, cotton was king in the trade of the young republic. The growing market for cotton and other American agricultural products led to an unprecedented expansion of agricultural settlement, mostly in the eastern half of the United States---west of the Appalachian Mountains and east of the Mississippi River.
The author mentions "wheat and wheat flour" in line 17 in order to
show that Americans exported more agricultural products than they imported.
show the increase in the amount of wheat products exported.
demonstrate the importance of cotton among American export products.
demonstrate that wheat farming was becoming more profitable.
Read the passage and choose the best answer for each question below.
By far the most important United States export product in the eighteenth and nineteenth centuries was cotton, favored by the European textile industry over flax or wool because it was easy to process and soft to tile touch. Mechanization of spinning and weaving allowed significant centralization and expansion in the textile industry during
this period, and at the same time the demand for cotton increased dramatically. American producers were able to meet this demand largely because of tile invention of the cotton gin by Eli Whitney in 1793. Cotton could be grown throughout the South, but separating the fiber – or lint – from the seed was a laborious process. Sea island cotton was relatively easy to process by hand, because its fibers were long and seeds were concentrated at the base of the flower, but it demanded a long growing season, available only along the nation's eastern seacoast. Short-staple cotton required a much shorter growing season, but the shortness of the fibers and their mixture with seeds meant that a worker could
hand-process only about one pound per day. Whitney's gin was a hand-powered machine with revolving drums and metal teeth to pull cotton fibers away from seeds. Using the gin, a worker could produce up to 50 pounds of lint a day. The later development of larger gins, powered by horses, water, or steam, multiplied productivity further.
The interaction of improved processing and high demand led to the rapid spread of the cultivation of cotton and to a surge in production. It became the main American export, dwarfing all others. In 1802, cotton composed 14 percent of total American exports by value. Cotton had a 36 percent share by 1810 and over a 50 percent share
in 1830. In 1860, 61 percent of the value of American exports was represented by cotton. In contrast, wheat and wheat flour composed only 6 percent of the value of American exports in that year. Clearly, cotton was king in the trade of the young republic. The growing market for cotton and other American agricultural products led to an unprecedented expansion of agricultural settlement, mostly in the eastern half of the United States---west of the Appalachian Mountains and east of the Mississippi River.
The word "unprecedented" in line 18 is closest in meaning to
slow
profitable
not seen before
never explained
Read the passage and choose the best answer for each question below.
By far the most important United States export product in the eighteenth and nineteenth centuries was cotton, favored by the European textile industry over flax or wool because it was easy to process and soft to tile touch. Mechanization of spinning and weaving allowed significant centralization and expansion in the textile industry during
this period, and at the same time the demand for cotton increased dramatically. American producers were able to meet this demand largely because of tile invention of the cotton gin by Eli Whitney in 1793. Cotton could be grown throughout the South, but separating the fiber – or lint – from the seed was a laborious process. Sea island cotton was relatively easy to process by hand, because its fibers were long and seeds were concentrated at the base of the flower, but it demanded a long growing season, available only along the nation's eastern seacoast. Short-staple cotton required a much shorter growing season, but the shortness of the fibers and their mixture with seeds meant that a worker could
hand-process only about one pound per day. Whitney's gin was a hand-powered machine with revolving drums and metal teeth to pull cotton fibers away from seeds. Using the gin, a worker could produce up to 50 pounds of lint a day. The later development of larger gins, powered by horses, water, or steam, multiplied productivity further.
The interaction of improved processing and high demand led to the rapid spread of the cultivation of cotton and to a surge in production. It became the main American export, dwarfing all others. In 1802, cotton composed 14 percent of total American exports by value. Cotton had a 36 percent share by 1810 and over a 50 percent share
in 1830. In 1860, 61 percent of the value of American exports was represented by cotton. In contrast, wheat and wheat flour composed only 6 percent of the value of American exports in that year. Clearly, cotton was king in the trade of the young republic. The growing market for cotton and other American agricultural products led to an unprecedented expansion of agricultural settlement, mostly in the eastern half of the United States---west of the Appalachian Mountains and east of the Mississippi River.
According to the passage, the Mississippi River was
one of the boundaries of a region where new agricultural settlement took place
a major source of water for agricultural crops
the primary route by which agricultural crops were transported
a main source of power for most agricultural machinery

