<u>Answer:</u>
The air is a <u>homogeneous mixture of gases</u> that make up the Earth's atmosphere, which remain around the planet by the attraction force of gravity.
Its properties changes with the altitude, the pressure, the temperature and the density. For example, there is a relation that is <u>inversely proportional</u> between the temperature and the air density.
<h2>When the temperature decreases the density increases.
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Therefore, the air in a cool region of the atmosphere will be denser than the air in a hot region of the atmosphere.
In other words:
<h2>The air in a cool region underneath cloud cover will have <em><u>a higher density than</u></em> a region with no cloud cover
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