The ends of a "parabolic" water tank are the shape of the region inside the graph ofy = x2for0 ≤ y ≤ 4; the cross sections parallel to the top of the tank (and the ground) are rectangles. At its center the tank is 4 feet deep and 4 feet across. The tank is 8 feet long. Rain has filled the tank and water is removed by pumping it up to a spout that is 5 feet above the top of the tank. Set up a definite integral to find the work W that is done to lower the water to a depth of 3 feet and then find the work. [Hint: You will need to integrate with respect to y.] Could you please explain the problem and how you have gotten the integral? I've seen similar ones, but I want to be sure I know how the numbers are found.