Question

We find it difficult to breathe when we climb mountains

Answer 1

Answer:

because atmospheric pressure decreases and oxygen density also decreases.

Answer 2

Explanation:

The Earth's gravity holds the oxygen (O2) close to the surface .Therefore there is more oxygen in the ground level and thereby there is a less oxygen when we go higher and higher or by simply the oxygen level is less with increase in altitude. So it is very difficult to breathe when we climb mountains

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