Answer:
Explanation:
There are three main sources of heat in the deep earth: (1) heat from when the planet formed and accreted, which has not yet been lost; (2) frictional heating, caused by denser core material sinking to the center of the planet; and (3) heat from the decay of radioactive elements.
To obtain oxygen.............
1.autotrophs
2.both autotrophs and heterotrophs
3.heterotrophs
4.autotrophs
5.autotrophs
6.both heterotrophs and autotrophs
The group under the grow lights recommended distance
hope this helps
