Piper was out at a restaurant for dinner when the bill came. Her dinner came to $16. After adding in a tip, before tax, she paid $18.72. Find the percent tip.

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.