Try another version of this question The volume of a cylinder of height `7` inches and radius `r` inches is given by the formula `V=7 pi r^2`. Which is the correct expression for `(dV)/dt`? Box 1: Select the best answer
Start by taking the derivative of the right hand side. We will apply the chain rule here. Note `pi` is just a number and can be viewed as a constant here.
`(dV)/dt=14 pi r (dr)/dt`