Two oil refineries each produce three grades of petroleum, A,B and C. At each refinery, the various grades of petroleum are produced in a single operation so that they are in fixed proportions. One operation at Refinery 1 produces 2 units of A,1 unit of B and 3 units of C. One operation at Refinery 2 produces 3 units of A,1 unit of B and 2 units of C. Refinery 1 charges $200 for one operation, and Refinery 2 charges $300 for one operation. A consumer needs at least 800 units of A,340 units of B and 820 units of C. How should the orders be placed if the consumer's needs are to be met most economically? (a) What can the manager ask for directly? Amount of C Number of operations at Refinery 1 Number of operations at Refinery 2 Amount of A Amount of B The manager orders x operations at Refinery 1 and y operations at Refinery 2. (b) Enter the total amount of A produced, as a function of x and y. (c) Enter the total amount of B produced, as a function of x and y. (d) Enter the total amount of C produced, as a function of x and y. (e) Each grade of oil, A,B and C, gives an inequality in x and y. Plot these inequalitios on a graph. Enter the coordinates of the com region (the feasible basic solutions). Enter them in incroasing order of their x-coordinate. For example, if one feasible basic solution is x another is x=5,y=0 and a third is x=2,y=3, you would onter (1,2),(2,3),(5,0) (1) Calculate the cost of each of these feasible basic solutions. Enter the cheapest coat