A swimming pool is circular with a 20-ft diameter. The depth is constant along east-west lines and increases linearly from 4 ft at the south end to 9...

A swimming pool is circular with a 20-ft diameter. The depth is constant along east-west lines and increases linearly from 4 ft at the south end to 9 ft at the north end. Find the volume of water in the pool. (Round the answer to the nearest whole number.)