When air descends it compresses. When the air compresses the molecules in the air knock into each other more often, increasing the tempertature.
Hope this helps
Answer:
soilds - close together arranged in a regular way
liquids - close together arranged in a random way
gases - far apart arranged in a random way
Explanation:
A biomass source is an natural material.
The sun is natural.
Manure is natural.
Wood Chips are natural.
Paper is natural and treated with unnatural substances.