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 39 to 43. It is a common misconception that greenhouse gasses only have detrimental effects on the Earth and our world would be a much better place without them. In actual fact, they play an indispensable role in our ecology. The Earth’s most abundant greenhouse gasses include carbon dioxide, methane, ozone, CFCs and water vapour, all of which can be ...

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 39 to 43.

It is a common misconception that greenhouse gasses only have detrimental effects on the Earth and our world would be a much better place without them. In actual fact, they play an indispensable role in our ecology. The Earth’s most abundant greenhouse gasses include carbon dioxide, methane, ozone, CFCs and water vapour, all of which can be found near the Earth surface. They absorb radiation, heating up the atmosphere. For example, carbon dioxide and water vapour take in infrared radiations coming to the earth. At the same time, they partly reflect these infrared radiations back to the earth’s surface. The process of radiation absorption maintains the temperature of the Earth in a way that makes the green planet habitable for mankind. Without these greenhouse gasses and their service, the Earth’s temperature would fall drastically and become uninhabitable.

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