Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions.

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 adapted. 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, even affect 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. The 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 that 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 revolutionary history may reflect a sequence of essentially random events.

Why is “plankton” mentioned?

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 31 to 35.

Just as you designate and separate your physical workspace, you should be clear about when you’re working and when you’re not. You’ll get your best work done and be most ready to transition back to the office if you stick with your regular hours. Plus, if your role is collaborative, being on the same schedule as your coworkers makes everything much easier.

“The biggest difference between working from home and working in the office is that you are in charge of your environment and have to treat yourself like an employee,” Yurovsky says. This means holding yourself accountable, but also recognizing when enough is enough, just as a good manager might. “If you feel yourself extending your work hours because you are not doing anything in the evening...tell yourself it’s time to put work away, recharge, and start tomorrow with a fresh mind. The work will be there in the morning.”

If you live with other people, this separation is even more critical. Communicate with the people whom you live with to establish boundaries so you can cut down on distractions during the workday—and then disconnect and give the people you care about your full attention. Having a separate time and space to work will allow you to be more present in your home life.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 31 to 35.

Just as you designate and separate your physical workspace, you should be clear about when you’re working and when you’re not. You’ll get your best work done and be most ready to transition back to the office if you stick with your regular hours. Plus, if your role is collaborative, being on the same schedule as your coworkers makes everything much easier.

“The biggest difference between working from home and working in the office is that you are in charge of your environment and have to treat yourself like an employee,” Yurovsky says. This means holding yourself accountable, but also recognizing when enough is enough, just as a good manager might. “If you feel yourself extending your work hours because you are not doing anything in the evening...tell yourself it’s time to put work away, recharge, and start tomorrow with a fresh mind. The work will be there in the morning.”

If you live with other people, this separation is even more critical. Communicate with the people whom you live with to establish boundaries so you can cut down on distractions during the workday—and then disconnect and give the people you care about your full attention. Having a separate time and space to work will allow you to be more present in your home life.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 31 to 35.

Just as you designate and separate your physical workspace, you should be clear about when you’re working and when you’re not. You’ll get your best work done and be most ready to transition back to the office if you stick with your regular hours. Plus, if your role is collaborative, being on the same schedule as your coworkers makes everything much easier.

“The biggest difference between working from home and working in the office is that you are in charge of your environment and have to treat yourself like an employee,” Yurovsky says. This means holding yourself accountable, but also recognizing when enough is enough, just as a good manager might. “If you feel yourself extending your work hours because you are not doing anything in the evening...tell yourself it’s time to put work away, recharge, and start tomorrow with a fresh mind. The work will be there in the morning.”

If you live with other people, this separation is even more critical. Communicate with the people whom you live with to establish boundaries so you can cut down on distractions during the workday—and then disconnect and give the people you care about your full attention. Having a separate time and space to work will allow you to be more present in your home life.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 31 to 35.

Just as you designate and separate your physical workspace, you should be clear about when you’re working and when you’re not. You’ll get your best work done and be most ready to transition back to the office if you stick with your regular hours. Plus, if your role is collaborative, being on the same schedule as your coworkers makes everything much easier.

“The biggest difference between working from home and working in the office is that you are in charge of your environment and have to treat yourself like an employee,” Yurovsky says. This means holding yourself accountable, but also recognizing when enough is enough, just as a good manager might. “If you feel yourself extending your work hours because you are not doing anything in the evening...tell yourself it’s time to put work away, recharge, and start tomorrow with a fresh mind. The work will be there in the morning.”

If you live with other people, this separation is even more critical. Communicate with the people whom you live with to establish boundaries so you can cut down on distractions during the workday—and then disconnect and give the people you care about your full attention. Having a separate time and space to work will allow you to be more present in your home life.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 31 to 35.

Just as you designate and separate your physical workspace, you should be clear about when you’re working and when you’re not. You’ll get your best work done and be most ready to transition back to the office if you stick with your regular hours. Plus, if your role is collaborative, being on the same schedule as your coworkers makes everything much easier.

“The biggest difference between working from home and working in the office is that you are in charge of your environment and have to treat yourself like an employee,” Yurovsky says. This means holding yourself accountable, but also recognizing when enough is enough, just as a good manager might. “If you feel yourself extending your work hours because you are not doing anything in the evening...tell yourself it’s time to put work away, recharge, and start tomorrow with a fresh mind. The work will be there in the morning.”

If you live with other people, this separation is even more critical. Communicate with the people whom you live with to establish boundaries so you can cut down on distractions during the workday—and then disconnect and give the people you care about your full attention. Having a separate time and space to work will allow you to be more present in your home life.

Read the following passage and mark the letter A, B, C, or D to indicate the correct word or phrase that best fits each of the numbered blanks.

Sir Isaac Newton, the English scientist and mathematician, was one of the most important figures of the 17th century scientific revolution. One of his greatest achievement was the discovery of the three laws of motion, (26) ______ are still used today. But he also had a very unusual personality. Some people would say he was actually insane.

His father died before he was born, and his mother soon remarried. The young Isaac hated his stepfather so much that he once (27) _____ to burn his house down - when his stepfather and mother were still inside! Fortunately he did not, and he went on to graduate from Cambridge without being thrown into prison.

Isaac's first published work was a theory of light and color. When another scientist wrote a paper criticizing this theory, Isaac flew into an uncontrollable rage. The scientist (28) ______ for the criticism was a man called Robert Hooke. He was head of the Royal Society, and one of the most respected scientists in the country. (29)_______, this made no difference to Isaac, who refused to speak to him for over a year.

The simple fact was that Isaac found it impossible to have a calm discussion with anyone. As soon as someone said something that he disagreed with, he would lose his temper. For this reason he lived a large part of his life isolated from (30) ______ scientists. It is unlikely that many of them complained.

Read the following passage and mark the letter A, B, C, or D to indicate the correct word or phrase that best fits each of the numbered blanks.

Sir Isaac Newton, the English scientist and mathematician, was one of the most important figures of the 17th century scientific revolution. One of his greatest achievement was the discovery of the three laws of motion, (26) ______ are still used today. But he also had a very unusual personality. Some people would say he was actually insane.

His father died before he was born, and his mother soon remarried. The young Isaac hated his stepfather so much that he once (27) _____ to burn his house down - when his stepfather and mother were still inside! Fortunately he did not, and he went on to graduate from Cambridge without being thrown into prison.

Isaac's first published work was a theory of light and color. When another scientist wrote a paper criticizing this theory, Isaac flew into an uncontrollable rage. The scientist (28) ______ for the criticism was a man called Robert Hooke. He was head of the Royal Society, and one of the most respected scientists in the country. (29)_______, this made no difference to Isaac, who refused to speak to him for over a year.

The simple fact was that Isaac found it impossible to have a calm discussion with anyone. As soon as someone said something that he disagreed with, he would lose his temper. For this reason he lived a large part of his life isolated from (30) ______ scientists. It is unlikely that many of them complained.

Read the following passage and mark the letter A, B, C, or D to indicate the correct word or phrase that best fits each of the numbered blanks.

Sir Isaac Newton, the English scientist and mathematician, was one of the most important figures of the 17th century scientific revolution. One of his greatest achievement was the discovery of the three laws of motion, (26) ______ are still used today. But he also had a very unusual personality. Some people would say he was actually insane.

His father died before he was born, and his mother soon remarried. The young Isaac hated his stepfather so much that he once (27) _____ to burn his house down - when his stepfather and mother were still inside! Fortunately he did not, and he went on to graduate from Cambridge without being thrown into prison.

Isaac's first published work was a theory of light and color. When another scientist wrote a paper criticizing this theory, Isaac flew into an uncontrollable rage. The scientist (28) ______ for the criticism was a man called Robert Hooke. He was head of the Royal Society, and one of the most respected scientists in the country. (29)_______, this made no difference to Isaac, who refused to speak to him for over a year.

The simple fact was that Isaac found it impossible to have a calm discussion with anyone. As soon as someone said something that he disagreed with, he would lose his temper. For this reason he lived a large part of his life isolated from (30) ______ scientists. It is unlikely that many of them complained.

Read the following passage and mark the letter A, B, C, or D to indicate the correct word or phrase that best fits each of the numbered blanks.

Sir Isaac Newton, the English scientist and mathematician, was one of the most important figures of the 17th century scientific revolution. One of his greatest achievement was the discovery of the three laws of motion, (26) ______ are still used today. But he also had a very unusual personality. Some people would say he was actually insane.

His father died before he was born, and his mother soon remarried. The young Isaac hated his stepfather so much that he once (27) _____ to burn his house down - when his stepfather and mother were still inside! Fortunately he did not, and he went on to graduate from Cambridge without being thrown into prison.

Isaac's first published work was a theory of light and color. When another scientist wrote a paper criticizing this theory, Isaac flew into an uncontrollable rage. The scientist (28) ______ for the criticism was a man called Robert Hooke. He was head of the Royal Society, and one of the most respected scientists in the country. (29)_______, this made no difference to Isaac, who refused to speak to him for over a year.

The simple fact was that Isaac found it impossible to have a calm discussion with anyone. As soon as someone said something that he disagreed with, he would lose his temper. For this reason he lived a large part of his life isolated from (30) ______ scientists. It is unlikely that many of them complained.

Read the following passage and mark the letter A, B, C, or D to indicate the correct word or phrase that best fits each of the numbered blanks.

Sir Isaac Newton, the English scientist and mathematician, was one of the most important figures of the 17th century scientific revolution. One of his greatest achievement was the discovery of the three laws of motion, (26) ______ are still used today. But he also had a very unusual personality. Some people would say he was actually insane.

His father died before he was born, and his mother soon remarried. The young Isaac hated his stepfather so much that he once (27) _____ to burn his house down - when his stepfather and mother were still inside! Fortunately he did not, and he went on to graduate from Cambridge without being thrown into prison.

Isaac's first published work was a theory of light and color. When another scientist wrote a paper criticizing this theory, Isaac flew into an uncontrollable rage. The scientist (28) ______ for the criticism was a man called Robert Hooke. He was head of the Royal Society, and one of the most respected scientists in the country. (29)_______, this made no difference to Isaac, who refused to speak to him for over a year.

The simple fact was that Isaac found it impossible to have a calm discussion with anyone. As soon as someone said something that he disagreed with, he would lose his temper. For this reason he lived a large part of his life isolated from (30) ______ scientists. It is unlikely that many of them complained.