The Total Number of People Who Have Seen a Newly $f(t)=5000\left(1-e^{-.2 t}\right)$

Essay

The total number of people who have seen a newly released movie at a particular theater chain follows the model $f(t)=5000\left(1-e^{-.2 t}\right)$ , where $f(t)$ is the number of people who have seen the movie after $t$ days. Use a calculator to graph $y=f(t)$ for $0 \leq t \leq 20$ , and determine $f^{\prime}(5)$ . What does $f^{\prime}(5)$ tell about the situation?