Problem: A cow is tied to the outside of a circular silo of diameter 30 ft with a rope that has length L = 10*Pi ft.Find the area of the region that is within the cow's reach for grazing.

How would I go about solving this one? I'm guessing I have to do something with polar coordinates and the area formula, but I couldn't figure out how to get an equation for the cow's grazing range. Thanks for the help!