Answer
See the explanation
Work Step by Step
a. $F(x)=$ $\begin{cases} (40-x)15& if& 0\lt x\lt40\\ 0 & if&40\leq x\leq65\\ (x-65)15&if&x\gt65 \end{cases}$
b. Since $0\lt30\lt40,$ $F(30)=(40-30)15=150,$
Since $40\lt50\lt65,$ $F(50)=0,$
Since $75\gt65,$ $F(75)=(75-65)15=150$
c. The higher or the lower the speed deviates from the permitted speed, the higher the fine is.
