A trough is 9m long, 5m wide, and 3m deep. The vertical cross-section of the trough parallel to an end is shaped like an isoceles triangle (with height 3m, and base, on top, of length 5m). The trough is full of water (density 1000kg/m³ and g = 9.8m/s² is the acceleration due to gravity).
Find the amount of work in joules required to empty the trough by pumping the water out of a spout 5m high.