A water tank has the shape of a right circular cone with its vertex down. Its altitude is 10 cm and theradius of the base is 15 cm. Water leaks out of the bottom at a constant rate of lcu.cm/sec. Water ispoured into the tank at a constant rate of C cu. cm/sec. Compute C so that the water level will berising at the rate of 4 cm/sec at the instant when the water is 2 cm deep.