Given the network shown below, where the labels next to the nodes are the supplies/demand. We wish to minimize the cost of this transshipment problem. Consider the darker arcs to be the spanning tree for this network. The flows for this spanning tree are given as the underlined amounts next to each arc. The numbers ($x, y) are the costs and the capacities on each arc.

Suppose we send 11 units from a, e to d, 10 units from a, b to d, and 10 units from a, b to f. Solve the minimum cost network flow using network simplex method.

10 31 ($5,35) ($11,11) 4,11) ($5,35) 10,20) ($15,25) ) ($5,30) ($14,36) 21