I'm totally lost.

A rain drop hitting a lake makes a circular ripple. If the radius, in inches, grows as a function of time in minutes according to r (t) = 35vt + 2, find the area of the ripple as a function of time. Find the area of the ripple at t = 2. Enter the exact answer. For the number , you can either type pi or you can click the button with * on it. Do not enter any commas in your answer. va la sin [a) A = in