The AMD Inc. made a contract with the government to supply 1200 microcomputers this year and 2500 next year. The company has the production capacity to make 1400 microcomputers each year, and it has already committed its production line for this level. Based on managerial decisions, the production line can be used for at most 80 overtime shifts each year, each shift costing the company an additional $20,000. In each overtime shift, 50 microcomputers can be manufactured. Units produced this year to meet next year's demand must be stored at a cost of $100 per unit. Formulate and solve a linear programming model to find the best production schedule that minimizes total costs. (Please write your notation, LP formulation explicitly, submit your managerial reports with computer models, solutions, answer and sensitivity reports attached.)