A company manufactures mechanical heart valves from the heart valves of pigs. Different heart operations require valves of different sizes. The company purchases pig valves from three different suppliers. The cost and size mix of the valves purchased from each supplier are given in the file P03_36.xlsx. This file also contains the maximum number of valves available from each supplier per month. Each month, the company places an order with each supplier. At least 1300 large, 900 medi- um, and 400 small valves must be purchased each month. a. Use Solver to determine how the company can minimize the cost of acquiring the needed valves. b. Use SolverTable to investigate the effect on total cost of increasing its minimal purchase requirements each month. Specifically, see how the total cost changes as the minimal purchase requirements of large, medium, and small valves all increase from their original values by the same percentage. Revise your model so that SolverTable can be used to investigate these changes when the percentage increase varies from 2% to 40% in increments of 2%

Problem 3.36(a) -Manufacturing Mechanical Heart Valves (p. 127) Inputs Supplier 1 Supplier 2 Supplier 3 \begin{tabular}{|l|l|c|} \multicolumn{1}{r|}{ Purchases } & & Available \\ \hline & = & & \\ \hline & >= & >= \\ \hline & & \\ \hline \end{tabular} Total cost