Why do you subtract exponents when dividing powers with same base

The quadratic function h(t)=-16.1t^2+150 choose the graph representation

The two square pyramids are similar. find the total volume of both pyramids if the ratio of their surface areas is 9/16

Compare the following pair of numbers a and b in three ways. a. find the ratio of a to b. b. find the ratio of b to a. c. complete the sentence: a is percent of b. a=120 and b=340 a. the ratio of a to b is . b. the ratio of b to a is . c. a is nothing percent of b.