7. First, solve the transportation problem below using the Intuitive Least Cost method. Then, use the Northwest Corner method to get a feasible starting solution, and apply the Stepping-Stone method to get the optimal solution. (20 points) Please show all calculations. Store A Store B Store C Supply 5 3 4 Plant 1 100 8 3 4 Plant 2 2 300 9 5 7 Plant 3 300 Demand 300 200 200 700 Store A 5 Store B 3 Store C 4 Supply 5 Plant 1 100 8 3 4 Plant 2 300 9 9 5 5 7 Plant 3 300 Demand 300 200 200 700 Store A Store C Supply 5 Store B 3 Plant 1 100 8 3 Plant 2 300 9 5 7 Plant 3 300 Demand 300 200 200 700 Supply Store A 5 Store B 3 Store C 4 3 Plant 1 1 100 00 8 3 4 Plant 2 300 9 5 7 Plant 3 3 300 Demand 300 200 200 700 Supply Store A 5 Store B 3 Store C 4 Plant 1 100 00 8 3 4 Plant N 300 9 5 7 Plant 3 300 Demand 300 200 200 700 Store A 5 Store B 3 Store C 4 Supply Plant 1 100 00 3 4 Plant 2 300 9 9 5 7 Plant 3 3 300 Demand 300 200 200 700