Calculus (Definite Integrals  Fluid Pressure)
posted by Casablanca .
The ends of a water trough have the shape of the region bounded by the graphs of y = x2 and y = 4 with x and y both measured in feet. To what depth must the trough be filled with water so that the force exerted by the water on either end of the trough is 779.423 lb? (Water has a density of 62.5 lb per cubic foot).

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