Objeotive function?

Variable bounds?

II. Ler's deal with a problem of an oil refinery planning. The processing stages of the refinery are depicted in the following figure. The 1s stage at the left performs a distillation of two types of crude oils (CR1 and CR2). The outputs of the distillation (P1 and P2) are transformed by different recipes to produce intermediate products ( P3 and P4). The final stage is blending the four intermediate products ( P1,P2,P3, and P4 ) into two final products ( F1 and F2 ). The prices for final products are \$31/unit and \$33/unit. The buying costs for two types of crude oils are $20 unit and $22 /unit, distillation costs for crude oils are $1.20 unit and $1.25/ unit, transformation costs for P1 and P2 through transformer1 are $0.50 and $0.52, and transformation costs for P1 and P2 through transformer2 are $0.61 and $0.68. Distillation process is performed without any loss of crude oils. Distilling CR1 by a unit, the refinery gets 0.48 unit of P1 and 0.46 unit of P2 and distilling a unit of CR2, it gets 0.49 unit of PI and 0.48 unit of P2. By transforming P1 and P2 through transformers 1 and 2 , it produces the following amount of P3 and P4 in table. Blending process is also performed without any loss of intermediate products. The refinery cannot buy two types of crude oils more than 180 units and 160 units, respectively. The sales of F1 should be between 105 and 135 and that of F2 should be between 45 and 80 . The decision variables consist of the quantity of two types of crude oils to buy, the quantity of crudes oils to distill, and the quantity of final products to sell in order to maximize the net revenue. 1. Formulate the above problem into LP. 2. Solve the LP model with LP Solve 3. Interpret the result of solution based on 5 factors of LP result