Today I’d like to begin a discussion on the problem of the heating up the earth. First, we’ll touch on the relationship between fluorocarbons and the ozone layer. You probably remember that the ozone layer is the protective shield around the earth. It is important to all life, because it filters out harmful ultraviolet light from the sun. Ozone itself, a form of oxygen, is regularly made by the action of the sun in the upper atmosphere. It is also regularly destroyed by natural chemical processes.

The problem now is that too much of the ozone layer is being destroyed. Scientists suspect that certain chemicals, such as fluorocarbons, are contributing to the depletion of the ozone layer. And how do we use fluorocarbons? The most common uses are in spray cans and cooling systems. The chemical pollution from these fluorocarbons can account for some of the ozone losses that have been reported. There are, however, new studies linking the sun itself to the depletion of the ozone layer. We’ll go into that new study more next time.

What will the speaker probably discuss next?

Câu hỏi liên quan

• The word “sustain” in paragraph 3 is closest in meaning to__________.

• What is the main idea of this passage?

• The word "vulnerable" in paragraph 4 is closest in meaning to .............

ZUNIA12

• When she decided to give up Facebook ..............

• What does the word “filters out” in paragraph 1 probably mean?

• In the paragraph following the passage most probably discusses  ..............

• Which of the following is NOT true about the concerns over roboties?

• According to the passage, approximately how many non-native users of English are there in the world today?

• It can be inferred from the passage that ___________.

• How did children feel when viewing a special series of 15-minute program at school?

• It can be inferred from the passage that the previous passage probably discussed ________.

• The word "perceive" in bold in paragraph 3 is closest in meaning to ..............

• The expression “readministration” in this passage refers to ................

• The word -lethal‖ in the second paragraph probably means ............

• According to the passage, travel books, biographies and memoirs ______.

• Which of the following is true, according to the passage?

• In the first paragraph, the word "emerged" is closest in meaning to ...........

• The passage suggests that the tsunami resulting from the Krakatoa volcano .....

• What does the passage mainly discuss?

• What will happen if a dodder plant starts growing where there are no other plants around?