A right cylindrical tank, with its axis vertical, is full of water (density δ = 62.4 pounds per cubic foot). The tank is 10 feet high and has radius 5 feet. Sasha and Zhenya have to pump all the water out of the tank. Sasha pumped until 3 feet of water remained in the tank, and then Zhenya pumped the remaining 3 feet of water out. Who did more work?