1. Three outlets A, B and C are supplied by three suppliers X, Y and Z. The table shows the cost, in pounds, of transporting each unit, the number of units required at each outlet and the number of units available at each supplier. X Y Z Demand A 9 10 12 50 B 11 8 7 40 10 12 8 30 Supply 30 50 40 a) Use the north-west corner method to obtain an initial solution. b) Use the least-cost method to obtain an initial solution. c) Find the total cost of each solution