Câu hỏi:
04/08/2023 2,426Read the passage below and choose the best answer to each question.
The air above our head is becoming cleaner. A breath of fresh air has been running right round the planet for the past five years. The planet is apparently purging itself of pollution. Paul Novell of the University of Colorado, the co-author of a report on this phenomenon says, “It seems as if the planet’s own cleaning service has suddenly got a new lease of life. Suddenly, there are a lot of changes going on up there”.
Estimates of the death toll from urban smog have been steadily rising, so the new cleaner trend could have significant consequences for life expectancy in cities as well as for the planet itself. The sudden and unexpected reversal of several decades of worsening pollution extends from the air in city streets to the remotest mid-Pacific Ocean and Antarctica.
Among the pollutants which have begun to disappear from the atmosphere are carbon monoxide, from car exhaust and burning rain forests, and methane from the guts of cattle, paddy fields, and gas fields. Even carbon dioxide, the main gas behind global warning, has fallen slightly.
There are two theories about why pollution is disappearing. First that there is less pollution to start with due to laws to cut down urban smogs and acid rain starting to have a global impact. Second, that the planet may be becoming more efficient at cleaning up.
The main planetary clean-up agent is a chemical called hydroxyl. It is present throughout the atmosphere in tiny quantities and removes most pollutants from the air by oxidizing them. The amount of hydroxyl in the air has fallen by a quarter in 1980s. Now it may be reviving for two reasons: ironically, because the ozone hole has expanded, letting in more ultraviolet radiation into the lower atmosphere, where it manufactures hydroxyl. Then the stricter controls on vehicle exhausts in America and Europe may have cut global carbon monoxide emissions, thereby allowing more hydroxyl to clean up other pollutants.
What is the main topic of the passage?
Sách mới 2k7: 30 đề đánh giá năng lực DHQG Hà Nội, Tp. Hồ Chí Minh, BKHN 2025 mới nhất (600 trang - chỉ từ 160k).
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Trả lời:
Chọn A
Câu hỏi cùng đoạn
Câu 2:
The word “purging” in line 2 is closest in meaning to __________.
Lời giải của GV VietJack
Chọn B
Câu 3:
According to the passage, life expectancy partly depends on people having __________.
Lời giải của GV VietJack
Chọn B
Câu 4:
The word “toll” in line 6 could best be replaced by__________.
Lời giải của GV VietJack
Chọn A
Câu 5:
What does the author suggest is the main cause of pollution reduction?
Lời giải của GV VietJack
Chọn A
Câu 6:
The word “it” in paragraph 5 refers to __________.
Lời giải của GV VietJack
Chọn D
Câu 7:
It can be inferred from the passage that the cleansing of the planet is __________.
Lời giải của GV VietJack
Chọn D
Câu 8:
Based on information in the passage, all of the following information referring to hydroxyl is true EXCEPT __________.
Lời giải của GV VietJack
Chọn C
Câu 9:
The word “reviving” in paragraph 5 is closest in meaning to __________.
Lời giải của GV VietJack
Chọn D
Câu 10:
The passage supports which of the following conclusions?
Lời giải của GV VietJack
Chọn A
Đã bán 152
Đã bán 114
Đã bán 132
Đã bán 47
CÂU HỎI HOT CÙNG CHỦ ĐỀ
Câu 1:
Câu 2:
Câu 3:
Listen to a radio interview, about an unusual hobby. Choose the correct answer from A, B or C for each of the following questions.
What is unusual about the cakes Darren makes?
Câu 4:
Câu 6:
UNICEF has assumed the responsibility of aiding children in need.
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