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प्रश्न
Observe the picture given in figure carefully and answer the following questions.
- What is covering the nose and mouth of the police man?
- Why is he putting a cover on his nose?
- Can you comment on air quality of the place shown in the figure?
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उत्तर
- The policeman is wearing a mask to cover his nose and mouth.
- He puts a cover on his nose to protect himself from dirt and polluted air. A mask avoids exposure to the harmful exhaust of vehicles, thus prevents the harmful gases and dust particles entering our body.
- The given figure shows a polluted area where the air quality is not good. It is due to the smoke and harmful gases such as carbon monoxide and sulphur dioxide emitted by the automobiles along with dust particles present in the air.
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