A circular swimming pool has a diameter of 16 meters, the sides are 4 meters high, and the depth of the water is 2.5 meters. The acceleration due to gravity is 9.8 and the density of water is 1000 .
How much work is required to:
(a) pump all of the water over the side?
(b) pump all of the water out of an outlet 2 m over the side?

I got the answer to part a. which is 627200pi*[(4*2.5 - (1/2)*(2.5)^2)-(0 - (1/2)*(0)^2)] J

It is b that I am not sure what to do. So, do I increase the diameter to 18 meters? and then do the problem again? Is there an easier way like adding on another calculation to the first one? Thanks