They are pumped across the mitochondrial inner membrane against their concentration gradient (to where their concentration is high); as the H+ ions flow back to where their concentration is low, they drive ATP synthase to form ATP
Acceleration is when something is being moved forward or back, motion is just movement, friction is two or more things rubbing together, so the answer should be B. gravity
When placed in a container, the heaviest (most dense) will sink to the bottom and the lightest (least dense) will rise to the top.
Therefore, Gasoline would rise to the top.
C.) Action force unless it has potential/stored enerygy
