Answer:
1. Earth's ozone layer is responsible for absorbing infrared and ultraviolet rays from the sun.
2. Changes in the composition of the atmosphere have caused gradual changes in earth's climate, causing changes in plant and animal life that contributed to mass extinctions.
3. Chemical chlorofluorocarbons (CFCs) have been banned and replaced with hydrochlorofluorocarbons (HCFCs).
4. Naturally occurring volcanic eruptions can produce large amounts of gases which contain sulfur. These gases accumulate in the atmosphere in the same way as man-made sulphuroxides.
Sorry, but after that I don't know.
Explanation:
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Answer:</h2><h2>
Cells exist by themselves such as bacteria....</h2>
Whilst Virus are non loving infectious particles and need a living host to reproduce.
