On Earth, water can exist as a solid, a liquid, or a gas. Why? Α.
Earth is at an ideal temperature due to its distance from the Sun.
B.
Earth rotates counterclockwise as viewed from above the North Pole.
C.
Earth is shaped like a sphere and revolves around the Sun.
O
D.
The Moon takes about 27 days to revolve around Earth.

Water can exist as a solid,a liquid, or a gas due to A.

Mitochondria produce atp, a high energy compound. atp is used for all sorts of enzyme-mediated reactions, such as making proteins/nucleotides/etc, certain compounds cross the cell membrane, muscles move, etc.  without this source of energy, a cell will die. it will not be able to repair itself, defend against pathogens, etc.