Question

radio station KROQ broadcast in all directions to a distance of 40 miles how many square miles are in the stations broadcast area

Answer 1

$\bf \textit{area of a circle}\\\\ A=\pi r^2~ \begin{cases} r=radius\\[-0.5em] \hrulefill\\ r=40 \end{cases}\implies A=\pi (40)^2\\\\\\ A=1600\pi \implies A\approx \stackrel{mi^2}{5026.5}$