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     In today's world, almost everyone knows that air pollution and water pollution are harmful to people'

health. However, not all the persons know that noise is also a kind of pollution, and this is harmful to

people' health, too.

     People who work and live under noisy conditions usually become deaf today. However, scientist believe

that 10 percent of workers in Britain are being deafened by the noise where they work. Many of the workers

who print newspapers and books, and who weave cloth become deaf. Quite a few people living near airports

also become deaf. Recently it was discovered that many teenagers in America could hear no better than

65-year-old persons, for these young people like to listen to pop music and pop music is a kind of noise,

Besides, noise produced by jet planes or machines will make people ill or even drive them mad.

     It is said a continuous noise of over 85 decibels can cause deafness. Now the government in many

countries have made laws to control noise and make it less than 85 decibels.

     In China, the government is trying to solve not only air and water pollution problems but also noise

problems.

1. The text is mainly about ______.

A. air pollution

B. water pollution

C. noise pollution

D. world pollution

2. According to the text, a continuous noise of ______ decibels can make people deaf.

A. less than 85

B. less than 65

C. about 65

D. more than 85

3. Ten percent of the workers in Britain are being deafened because ______.

A. they are working in noisy places

B. they often listen to pop music

C. they are busy in listening to other's talk

D. they live near airports

4. The government of China is trying to solve ______.

A. only air pollution

B. only air and water pollution

C. only water pollution

D. air, water and noise pollution