1. The manager of an oil refinery must decide on the optimal mix of two possible blending processes of which the input and output per production run are given as follows: Process Input Output Units Crude Crude Gasoline Gasoline A B X Y 1 5 3 50 8 2 4 5 4 4 The maximum amount available of crude A and B are 200 units and 150 units respectively. Market requirements show that at least 100 units of gasoline X and 80 units of gasoline Y must be produced. The profit per production run from process 1 and process 2 are Rs. 300 and Rs. 400 respectively. Formulate this problem as a linear programming model.