Average Rate of Change Practice Test

A runner’s distance from the starting line (in miles) after $t$ hours is given by $d(t)=6t+2$. What is the average rate of change of $d(t)$ from $t=1$ to $t=4$? Give your answer in mi/hr.

For the linear function $p(x)=4x-7$, what is the average rate of change of $p(x)$ from $x=-2$ to $x=3$?