Question

6. Why does the density of air become lower in the upper part of the atmosphere?​

Answer 1

Explanation:

The density of air decreases with height. There are two reasons: at higher altitudes, there is less air pushing down from above, and gravity is weaker farther from Earth's center. So at higher altitudes, air molecules can spread out more, and air density decreases (Figure below).

hope it's helpful

please mark my answer as brainlist