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Otrada [13]
3 years ago
8

Which of the following statements about the composition of earths atmosphere is true?

Biology
2 answers:
melamori03 [73]3 years ago
8 0

Answer:

b) earths atmosphere contains 21% oxygen.

Explanation:

The atmosphere is the envelope of air surrounding the Earth. The air composed of gases. In the atmosphere, the percentage of different gases differ. Nitrogen comprises 78.08 %, oxygen is 20.95%, and carbon dioxide is another important gas which consists of 0.036%. In the atmosphere, water vapour is 0 to 4%.

It is divided up into layers or spheres such as troposphere, stratosphere, mesosphere. The troposphere is lowermost layers in which living organisms found. In the stratosphere, the ozone layer is present which absorbs harmful ultraviolet radiation (UV rays) which are coming from the sun. So, it protects life from its harmful effect.  

Luden [163]3 years ago
5 0
B because a and c are incorrect and in letter d it states earth has no protection at all. And it DOES have protection B is most definitely true
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3 years ago
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8 0
2 years ago
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Dmitrij [34]

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8 0
3 years ago
Cause somebody plz help me
svetlana [45]
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7 0
3 years ago
Jill uses a magnet to pick up a nail. Then, she touches the nail to a paper clip and picks up the paper clip. What will most lik
Lemur [1.5K]

Answer:

C but see below.

Explanation:

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Of the four answers you have given us, I would agree with C.  But as I've argued above, the real reason is likely there.

3 0
3 years ago
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