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.

The elements other than hydrogen and helium exist in such small quantities that it is accurate to say that the universe is somewhat more than 25 percent helium by weight and somewhat less than 75 percent hydrogen.

Astronomers have measured the abundance of helium throughout our galaxy and in other galaxies as well. Helium has been found in old stars, in relatively young ones, in interstellar gas, and in the distant objects known as quasars. Helium nuclei have also been found to be constituents of cosmic rays that fall on the earth (cosmic rays are not really a form of radiation; they consist of rapidly moving particles of numerous different kinds). It doesn’t seem to make very much difference where the helium is found. Its relative abundance never seems to vary much. In some places, there may be slightly more of it; in others, slightly less, but the ratio of helium to hydrogen nuclei always remains about the same.

Helium is created in stars. In fact, nuclear reactions that convert hydrogen to helium are responsible for most of the energy that stars produce. However, the amount of helium that could have been produced in this manner can be calculated, and it turns out to be no more than a few percent. The universe has not existed long enough for this figure to be significant greater. Consequently, if the universe is somewhat more than 25 percent helium now, then it must have been about 25 percent helium at a time near the beginning.

However, when the universe was less than one minute old, no helium could have existed. Calculations indicate that before this time temperature were too high and particles of matter were moving around much too rapidly. It was only after the one-minute point that helium could exist. By this time, the universe had cooled so sufficiently that neutrons and protons could stick together. But the nuclear reactions that led to the formations of helium went on for only relatively short time. By the time the universe was a few minutes old, helium production had effectively ceased.

What does the passage mainly explain? 

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.