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Additional Work problems. 1) A cylindrical water tank 12 feet high with a radius of 8 feet is buried so that the top of the tank is 3 feet below ground level. How much work is done in pumping a full tank of water up to ground level? (The water weighs 62.4 pounds per cubic foot). 15 2 Ans W = π (8) ∫ (62.4)xdx = 431,308π ft − lb 3 2) A particle is moved along the x‐ axis by a force that measures 8/(1 + x)2 pounds at a point x feet from the origin. Find the work done in moving the particle from the origin to a distance of 12 feet. 12 Ans : W = 8 ∫0 (1 + x )2 dx = 7.38 ft − lb