Mathematics

Mathematics

Problem

A circular oil spill is shrinking such that the radius decreases at a constant rate of 0.30\,cm/s. At the moment when the radius is 4\,cm, which of the following gives the instantaneous rate of change of the area of the spill? a) dAdt=2.4π cm2/s\displaystyle \frac{dA}{dt}=2.4\pi\text{ cm}^2/\text{s} b) dAdt=−0.60π cm2/s\displaystyle \frac{dA}{dt}=-0.60\pi\text{ cm}^2/\text{s} c) dAdt=−2.4π cm2/s\displaystyle \frac{dA}{dt}=-2.4\pi\text{ cm}^2/\text{s} d) dAdt=−4.8π cm2/s\displaystyle \frac{dA}{dt}=-4.8\pi\text{ cm}^2/\text{s}

Browse the problem library