A company manufactures computers in factories located in Pittsburgh and Kansas City. These are shipped to regional distribution centers in Chicago, Phoenix, and Philadelphia. Ultimately, they are delivered to supply houses in New York and Los Angeles. The available supplies at the factories, demands at the final destinations, and shipping costs are illustrated in the table below. Let (1) = Pittsburgh, (2) = Kansas City, (3) = Chicago, (4) = Phoenix, (5) = Philadelphia, (6) = New York, and (7) = Los Angeles. To From Chicago Phoenix Philadelphia New York Los Angeles Supply Pittsburgh $4 $8 $2 1500 Kansas City $3 $6 $5 1000 Chicago 5 7 Phoenix 8 3 Philadelphia 2 9 Demand 1200 800 Please select all incorrect constraints. a. x14 x24 = x46 x47 b. x23 x24 x25 1000 c. x36 x46 x56 1200 d. x13 x23 = x36 x47 e. x13 x14 x15 1500 f. x15 x25 = x56 x57