A concrete company transports concrete from three plants to three construction sites. The supply capacities of the three plants, the demand requirements at the three sites, and the transportation costs per ton are as follows: Construction Site DC A B C Supply 1 $8 $5 $6 120 2 3 15 10 12 180 3 9 10 80 Demand (tons) 150 70 100 Determine the linear programming model formulation for this problem. The constraint that represents the quantity supplied by source 1 is: (Note: refer to slide # 11 Example Problem for the clue) 8xA1+5XA2+6xA3 120 8X1A+5X1B + 6x1c = 120 X1A+X1B+X1c = 120 X1A+X18+X1cs 120