The American Edwards Laboratories (AEL) manufactures artificial human heart valves from pig hearts. One of the things making planning complex is that the size of pig hearts is highly variable, depending on breed, age when slaughtered, feed mix, and so on. The following table shows the fraction of hearts from suppliers j {1, . . . , 5} yielding each of the valve sizes i {1, . . . , 7} along with the maximum quantity available from each supplier per week and the unit cost of hearts obtained