The ozone layer: Between 15 and 50 km above the earth is a thin layer of gas called 'ozone'. It protects the earth from most of the sun's harmful ultraviolet radiation. Too much radiation causes blindness in animals and skin cancer in people. In 1985, scientists discovered a hole in the ozone layer in the Antartica. They have recently discovered a smaller hole over the arctic. The ozone layer is also becoming thinner over other locations of the earth too. Scientists believe that over the last 10 years about 30% of the ozone layer has disappeared. This damage is caused by chemicals. Choose the right statement(s) from the following.

Q.

We are living in the midst of a great chemical experiment, and some serious consequences are becoming apparent to scientists. More than two billion pounds of chemicals are spewed into the air each year, which are brewing a disastrous stew. The greatest consequences of the atmosphere crisis may be global warming and ozone depletion. The Earth appears to be warming due to the greenhouse effect. Scientists estimate that average temperature could climb about 20C in 20 years.Global warming is the predicted result of the greenhouse effect, created by the greenhouse gasses, such as carbon dioxide and methane, in the atmosphere. This change in the global climate would have disastrous results including drought, coastal flooding and increased species extinction. Also, the scientists have discovered a hole in the ozone layer. The ozone layer is the only protection for life on Earth against deadly ultraviolet radiation from the Sun. Once the ozone layer is completely destroyed, all life on the Earth will cease to exist, killed by the deadly radiation. The planet will become a barren rock devoid of all life. And when this happens the process of industrialisation would have to take the blame, which has resulted in increased use of fossil fuels such as coal, petroleum and diesel.

Q. Which of the following can be inferred from the given passage?

Q. Read the following statements:
i. Ozone is found mostly in the stratosphere
ii. Ozone layer lies 55-75 km above the surface of the earth.
iii. Ozone absorbs ultraviolet radiation from the Sun.
iv. Ozone layer has no significance for life on the earth.
Which set of the statements is correct?

Q. Ozone layer protects the earth from harmful ultraviolet rays.

Q. Name the radiations absorbed by ozone layer. What would happen to living ones on earth of ozone layer around us disappears ?