It’s the study of people and the outside world
First, he should measure how long it takes for the liquid to become clear if X and Y are mixed together. Then, he should measure how long it takes if he also adds substance A to X and Y. He will find out if substance A is a catalyst. hope this helps :)
False.
There are several good mutations that have ensured the survival of species. Typically helpful mutations help the creature adapt to its environment or protect itself from predators.
I hope this helps! :)