## Calculus 8th Edition

$4\pi$ centimeters
We use the formula $s=θr$ $θ$ must be in radians. It is given in degrees. We convert from radians to degrees: $72°\times\frac{\pi}{180}=\frac{2\pi}{5}$ Plug in given values and simplify: $s=\frac{2\pi}{5}(10)=4\pi$ centimeters