Paving a walkway: Current plans call for building a circular fountain 6 m in diameter with...

Paving a walkway: Current plans call for building a circular fountain 6 m in diameter with a circular walkway around it that is 1.5 m wide. (a) What is the approximate area of the walkway? (b) If the concrete for the walkway is to be 6 cm deep, what volume of cement must be used 11 cm = 0.01 m)?