Ascientist randomly divided a group of 100 lab rats into two groups of 50. one group was fed regular rat chow while the other was fed the same amount of rat chow with added ddt. both groups were housed in the same room with the same environmental conditions. at the end of the experiment, rats were weighed and the mean difference calculated.

answer: i say it foxes

explanation:

you need to give us the answer options to for me to offical decide.

yes!

explanation:

because it has a type of fat that can make you extremely sick

its temperature is increasing. this causes molecular vibrations to increase.

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.