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प्रश्न
Study the following statements about ozone:
- It is essential for breathing of living organisms.
- It is used to disinfect water.
- It absorbs ultraviolet rays.
- Its proportion in air is about 3%.
Which of these statements are correct?
पर्याय
(a), (b) and (c)
(b) and (c)
(a) and (d)
All four
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उत्तर
(b) and (c)
Explanation:
- Statement (a) is incorrect because oxygen, not ozone, is essential for breathing.
- Statement (b) is correct as ozone is used to disinfect water.
- Statement (c) is correct because ozone absorbs ultraviolet rays.
- Statement (d) is incorrect because the proportion of ozone in the air is much less than 3%.
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