express the given function h as a composition of two functions f and g so that h(x)=(f o g) (x) where one of the functions is 2x-6

Describe the end behavior of the function below. f(x)=(2/3)^x-2 a. as x increases, f(x) approaches infinity. b. as x decreases, f(x) approaches 2. c. as x increases, f(x) approaches -2. d. as x decreases, f(x) approaches negative infinity.