Mathematics

Problem

The circumference of a circle increases at a constant rate of

0.5\,\text{cm/s}

. Find the rate at which its area is increasing when the radius is

10\,\text{cm}

. a)

5\pi\,\text{cm}^{2}/\text{s}

10\pi\,\text{cm}^{2}/\text{s}

5\,\text{cm}^{2}/\text{s}

10\,\text{cm}^{2}/\text{s}