Is a rule of matching elements of two sets of numbers in which an input value from the first set has only one output value in the second set.

c

step-by-step explanation:

i think da answer is

d.square root of 3

i think you would have to divide the money he had saved, which is $2,000 by the time he plans on exercising which is 40 hours, and the answer you get should tell you the answer to your question.

f(x) is   are being squared

g(x) is   increasing by 2

h(x) is adding .25 each time

k(x) is taking the square root

f(x) and k(x) are exponential functions