work = integral of WALT
W = weight density, 62 lbs/ft^3
A = horizontal cross-sectional area of a representative "slab" of liquid in terms of y ...
area =
L = vertical distance to lift a representative "slab" to the top,
T = "slab" thickness ...
A trough is feet long and foot high. The vertical cross-section of the trough parallel to an end is shaped like the graph of from to . The trough is full of water. Find the amount of work in foot-pounds required to empty the trough by pumping the water over the top. Note: The weight of water is pounds per cubic foot.