**(a)** The tank is full of water and the water is to be
pumped over the top of the tank.

Work =

(include units)

**(b)** The tank is full of water and the water must be
pumped to a height 6 ft above the top of the tank.

Work =

(include units)

**(c)** The depth of water in the tank is 6 ft and the
water must be pumped over the top of the tank.

Work =

(include units)