7 A trough has a trapezoidal cross section with a height of 7 m and horizontal sides of width m and 7 m. Assume the length of the trough is 14 m. See the figure to the right. Complete parts (a) and (b) below. 2 7 m 7 m 3.5 m 14 m 1 (Simplify your answer. Use integers or fractions for any numbers in the expression.) Set up the integral that gives the work required to pump the water out of the tank. Use increasing limits of integration. Select the correct choice below and fill in the answer boxes to complete your choice. (Type exact answers.) OA. SO dx 68600 (2-2) dy 7 B. S (6860 0 mately of work is required to pump the water out of the trough. the math palette as needed. Round to six decimal places as needed.)