..7 ...8 ... 9 ...10 ...QUESTION VII

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Question VII: Read the following passage and choose the correct answer ( marked A, B,

C or D).

Today, I’d like to begin a discussion on the problem of the heating up of the earth. First,

we’ll touch on the relationship between flourocarbons and the ozone layer. You probably

remember that the ozone layer is the protective shield around the earth. It is important to

our 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 flourocarbons? The most common uses are in spray

cans and cooling systems. The chemical pollution from these flourocarbons 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.