United Aluminum Company of Cincinnati produces three grades(high medium low) of aluminum at two mills. Each mill has adifferent production capacity (in tons per day) for each grade asfollows: Mill Aluminum Grade 1 2 High 6 2 Medium 2 2 Low 4 10 Thecompany has contracted with a manufacturing firm to supply at least12 tons of high-grade aluminum 8 tons of medium-grade aluminumand 5 tons of low-grade aluminum. It costs United $6000 per day tooperate mill 1 and $7000 per day to operate mill 2. The companywants to know the number of days to operate each mill to meet thecontract at minimum cost. a. Formulate a linear programming modelfor this problem. b. Solve this problem by using the computer.