a boy jumped into a lake causing his body temperature to decrease. as a result his muscles blood vessels and nervous system work together to restor his body temperature this is an example of what process

d. planting trees

the trees take in carbon to make oxygen.

it provides an alternative energy pathway for the reaction to proceed.

a catalyst is a substance that speeds up the rate of a chemical reaction but is not consumed during the course of the reaction.

catalysts increase the rate of reaction without being used up. they do this by lowering the activation energy needed. with a catalyst, more collisions result in a reaction, so the rate of reaction increases. different reactions need different catalysts.

a catalyst works by providing an alternative reaction pathway to the reaction product. the rate of the reaction is increased as this alternative route has a lower activation energy than the reaction route not mediated by the catalyst.

i think the answer is composed of atoms