1. A diet program is being prepared for the Dharma Putera dormitory, Gadjah Mada University . The goal is to feed the Students at the lowest cost, but the meals should have between 1,800 and 3,600 calories. No more than 1,400 calories can be starch, and no less than 400 can be protein. A varied diet should be made from two foods: A and B . Food A costs $0.75 per pound and contains 600 calories, 400 of which are protein and 200 starch. No more than two pounds of food A may be used per resident. Food B costs $0.15 per pound and contains 900 calories, 700 of which are starch, 100 are protein, and 100 are fat.
2. Write an equation that represents this information???

Solve the problem graphically for the amount of each food that should be used?..................................