Task 3 (6 Mei 2020)

With which of the following is the passage primarily concerned?

According to the best evidence gathered by space probes and astronomers, Mars is an inhospitable planet, more similar to Earth’s Moon than to Earth itself—a dry, stark, seemingly lifeless world. Mars’ air pressure is equal to Earth’s at an altitude of 100,000 feet. The air there is 95 percent carbon dioxide. Mars has no ozone layer to screen out the sun’s lethal radiation. Daytime temperatures may reach above freezing, but because the planet is blanketed by the mere wisp of an atmosphere, the heat radiates back into space. Even at the equator, the temperature drops to −50°C (−60°F) at night. Today there is no liquid water, although valleys and channels on the surface show evidence of having been carved by running water. The polar ice caps are made of frozen water and carbon dioxide, and water may be frozen in the ground as permafrost.

Despite these difficult conditions, certain scientists believe that there is a possibility of transforming Mars into a more Earth-like planet. Nuclear reactors might be used to melt frozen gases and eventually build up the atmosphere. This in turn could create a greenhouse effect that would stop heat from radiating back into space. Liquid water could be thawed to form a polar ocean. Once enough ice has melted, suitable plants could be introduced to build up the level of oxygen in the atmosphere so that, in time, the planet would support animal life from Earth and even permanent human colonies. “This was once thought to be so far in the future as to be irrelevant,” said Christopher McKay, a research scientist at the National Aeronautics and Space Administration. “But now it’s starting to look practical. We could begin work in four or five decades.”

The idea of “terra-forming” Mars, as enthusiasts call it, has its roots in science fiction. But as researchers develop a more profound understanding of how Earth’s ecology supports life, they have begun to see how it may be possible to create similar conditions on Mars. Don’t plan on homesteading on Mars any time soon, though. The process could take hundreds or even thousands of years to complete, and the cost would be staggering.

• The possibility of changing the Martian environment

• The challenge of interplanetary travel

• The advantages of establishing colonies on Mars

• The need to study the Martian ecology

The word stark in the first paragraph is closest in meaning to

According to the best evidence gathered by space probes and astronomers, Mars is an inhospitable planet, more similar to Earth’s Moon than to Earth itself—a dry, stark, seemingly lifeless world. Mars’ air pressure is equal to Earth’s at an altitude of 100,000 feet. The air there is 95 percent carbon dioxide. Mars has no ozone layer to screen out the sun’s lethal radiation. Daytime temperatures may reach above freezing, but because the planet is blanketed by the mere wisp of an atmosphere, the heat radiates back into space. Even at the equator, the temperature drops to −50°C (−60°F) at night. Today there is no liquid water, although valleys and channels on the surface show evidence of having been carved by running water. The polar ice caps are made of frozen water and carbon dioxide, and water may be frozen in the ground as permafrost.

• harsh.

• unknown.

• dark.

• distant.

The word there in the first paragraph refers to

According to the best evidence gathered by space probes and astronomers, Mars is an inhospitable planet, more similar to Earth’s Moon than to Earth itself—a dry, stark, seemingly lifeless world. Mars’ air pressure is equal to Earth’s at an altitude of 100,000 feet. The air there is 95 percent carbon dioxide. Mars has no ozone layer to screen out the sun’s lethal radiation. Daytime temperatures may reach above freezing, but because the planet is blanketed by the mere wisp of an atmosphere, the heat radiates back into space. Even at the equator, the temperature drops to −50°C (−60°F) at night. Today there is no liquid water, although valleys and channels on the surface show evidence of having been carved by running water. The polar ice caps are made of frozen water and carbon dioxide, and water may be frozen in the ground as permafrost.

• a point 100 miles above the earth

• the earth’s moon.

• Mars.

• outer space.

According to the passage, the Martian atmosphere today consists mainly of

According to the best evidence gathered by space probes and astronomers, Mars is an inhospitable planet, more similar to Earth’s Moon than to Earth itself—a dry, stark, seemingly lifeless world. Mars’ air pressure is equal to Earth’s at an altitude of 100,000 feet. The air there is 95 percent carbon dioxide. Mars has no ozone layer to screen out the sun’s lethal radiation. Daytime temperatures may reach above freezing, but because the planet is blanketed by the mere wisp of an atmosphere, the heat radiates back into space. Even at the equator, the temperature drops to −50°C (−60°F) at night. Today there is no liquid water, although valleys and channels on the surface show evidence of having been carved by running water. The polar ice caps are made of frozen water and carbon dioxide, and water may be frozen in the ground as permafrost.

Despite these difficult conditions, certain scientists believe that there is a possibility of transforming Mars into a more Earth-like planet. Nuclear reactors might be used to melt frozen gases and eventually build up the atmosphere. This in turn could create a greenhouse effect that would stop heat from radiating back into space. Liquid water could be thawed to form a polar ocean. Once enough ice has melted, suitable plants could be introduced to build up the level of oxygen in the atmosphere so that, in time, the planet would support animal life from Earth and even permanent human colonies. “This was once thought to be so far in the future as to be irrelevant,” said Christopher McKay, a research scientist at the National Aeronautics and Space Administration. “But now it’s starting to look practical. We could begin work in four or five decades.”

The idea of “terra-forming” Mars, as enthusiasts call it, has its roots in science fiction. But as researchers develop a more profound understanding of how Earth’s ecology supports life, they have begun to see how it may be possible to create similar conditions on Mars. Don’t plan on homesteading on Mars any time soon, though. The process could take hundreds or even thousands of years to complete, and the cost would be staggering.

• (A) carbon dioxide.

• (B) oxygen.

• (C) ozone.

• (D) water vapor.

Underline the sentence in the first paragraph that explains why Mars is so cold at night.

According to the best evidence gathered by space probes and astronomers, Mars is an inhospitable planet, more similar to Earth’s Moon than to Earth itself—a dry, stark, seemingly lifeless world. Mars’ air pressure is equal to Earth’s at an altitude of 100,000 feet. The air there is 95 percent carbon dioxide. Mars has no ozone layer to screen out the sun’s lethal radiation. Daytime temperatures may reach above freezing, but because the planet is blanketed by the mere wisp of an atmosphere, the heat radiates back into space. Even at the equator, the temperature drops to −50°C (−60°F) at night. Today there is no liquid water, although valleys and channels on the surface show evidence of having been carved by running water. The polar ice caps are made of frozen water and carbon dioxide, and water may be frozen in the ground as permafrost.

• Mars’ air pressure is equal to Earth’s at an altitude of 100,000 feet

• The polar ice caps are made of frozen water and carbon dioxide, and water may be frozen in the ground as permafrost.

• Daytime temperatures may reach above freezing, but because the planet is blanketed by the mere wisp of an atmosphere, the heat radiates back into space.

• Even at the equator, the temperature drops to −50°C (−60°F) at night.

Which of the following does the author NOT list as a characteristic of the planet Mars that would make colonization difficult?

According to the best evidence gathered by space probes and astronomers, Mars is an inhospitable planet, more similar to Earth’s Moon than to Earth itself—a dry, stark, seemingly lifeless world. Mars’ air pressure is equal to Earth’s at an altitude of 100,000 feet. The air there is 95 percent carbon dioxide. Mars has no ozone layer to screen out the sun’s lethal radiation. Daytime temperatures may reach above freezing, but because the planet is blanketed by the mere wisp of an atmosphere, the heat radiates back into space. Even at the equator, the temperature drops to −50°C (−60°F) at night. Today there is no liquid water, although valleys and channels on the surface show evidence of having been carved by running water. The polar ice caps are made of frozen water and carbon dioxide, and water may be frozen in the ground as permafrost.

Despite these difficult conditions, certain scientists believe that there is a possibility of transforming Mars into a more Earth-like planet. Nuclear reactors might be used to melt frozen gases and eventually build up the atmosphere. This in turn could create a greenhouse effect that would stop heat from radiating back into space. Liquid water could be thawed to form a polar ocean. Once enough ice has melted, suitable plants could be introduced to build up the level of oxygen in the atmosphere so that, in time, the planet would support animal life from Earth and even permanent human colonies. “This was once thought to be so far in the future as to be irrelevant,” said Christopher McKay, a research scientist at the National Aeronautics and Space Administration. “But now it’s starting to look practical. We could begin work in four or five decades.”

The idea of “terra-forming” Mars, as enthusiasts call it, has its roots in science fiction. But as researchers develop a more profound understanding of how Earth’s ecology supports life, they have begun to see how it may be possible to create similar conditions on Mars. Don’t plan on homesteading on Mars any time soon, though. The process could take hundreds or even thousands of years to complete, and the cost would be staggering.

• (A) There is little liquid water.

• (B) Daytime temperatures are dangerously high.

• (C) The sun’s rays are deadly.

• (D) Nighttime temperatures are extremely low.

It can be inferred from the passage that the greenhouse effect mentioned in the second paragraph is

Despite these difficult conditions, certain scientists believe that there is a possibility of transforming Mars into a more Earth-like planet. Nuclear reactors might be used to melt frozen gases and eventually build up the atmosphere. This in turn could create a greenhouse effect that would stop heat from radiating back into space. Liquid water could be thawed to form a polar ocean. Once enough ice has melted, suitable plants could be introduced to build up the level of oxygen in the atmosphere so that, in time, the planet would support animal life from Earth and even permanent human colonies. “This was once thought to be so far in the future as to be irrelevant,” said Christopher McKay, a research scientist at the National Aeronautics and Space Administration. “But now it’s starting to look practical. We could begin work in four or five decades.”

• (A) the direct result of nuclear reactions.

• (B) the cause of low temperatures on Mars.

• (C) caused by the introduction of green plants.

• (D) a possible means of warming Mars.

Look at the word thawed in the bold text below:

Frozen water could be thawed to form a polar ocean. Once enough ice has melted, suitable plants could be introduced to build up the level of oxygen in the atmosphere so that, in time, the planet would support animal life from Earth and even permanent human colonies.

Underline the word or phrase in the bold text that has the same meaning as thawed.

• permanent

• melted

• introduced

• enough

Look at the word feasible in the bold text below:

"Not many years ago, no one would have considered this a viable plan,” said Christopher McKay, a research scientist at the National Aeronautics and Space Administration. “But now it’s starting to look feasible. We could begin work in four or five decades.”

Underline the word or phrase in the bold text that has the same meaning as feasible.

• research

• plan

• viable

• considered

According to Christopher McKay, the possibility of transforming Mars

According to the best evidence gathered by space probes and astronomers, Mars is an inhospitable planet, more similar to Earth’s Moon than to Earth itself—a dry, stark, seemingly lifeless world. Mars’ air pressure is equal to Earth’s at an altitude of 100,000 feet. The air there is 95 percent carbon dioxide. Mars has no ozone layer to screen out the sun’s lethal radiation. Daytime temperatures may reach above freezing, but because the planet is blanketed by the mere wisp of an atmosphere, the heat radiates back into space. Even at the equator, the temperature drops to −50°C (−60°F) at night. Today there is no liquid water, although valleys and channels on the surface show evidence of having been carved by running water. The polar ice caps are made of frozen water and carbon dioxide, and water may be frozen in the ground as permafrost.

Despite these difficult conditions, certain scientists believe that there is a possibility of transforming Mars into a more Earth-like planet. Nuclear reactors might be used to melt frozen gases and eventually build up the atmosphere. This in turn could create a greenhouse effect that would stop heat from radiating back into space. Liquid water could be thawed to form a polar ocean. Once enough ice has melted, suitable plants could be introduced to build up the level of oxygen in the atmosphere so that, in time, the planet would support animal life from Earth and even permanent human colonies. “This was once thought to be so far in the future as to be irrelevant,” said Christopher McKay, a research scientist at the National Aeronautics and Space Administration. “But now it’s starting to look practical. We could begin work in four or five decades.”

The idea of “terra-forming” Mars, as enthusiasts call it, has its roots in science fiction. But as researchers develop a more profound understanding of how Earth’s ecology supports life, they have begun to see how it may be possible to create similar conditions on Mars. Don’t plan on homesteading on Mars any time soon, though. The process could take hundreds or even thousands of years to complete, and the cost would be staggering.

• (A) could only occur in science fiction stories.

• (B) will not begin for hundreds, even thousands of years.

• (C) is completely impractical.

• (D) could be started in forty to fifty years.