Solve this problem as an integer programming displaying the decision variables, objective function, constraints, and final answer using excel or lingo.

4. (25 pts) An engineering company produces tivo products Pl and P2. Each unit of product P1 requires 2 h of engineering service and 5 h of machining time One unit of P2 requires 3 h of engineering service and 8 h of machining time. There are 135 h of engineering and 600 h of machining time available. The cost of production is a step function as follows. The selling price for product P1 and P2 is $15 and $12, respectively. Formulate an integer programming model to maximize the total profit. Product Production (unita) Unit cost (3) 0-40 11 PI 41-100 9 0-49 10 P2 50-100 8