2 a Find the dual of the LP that was used to find the length of the critical path for Example 6 of Section 8.4.

b Show that the answer in part

(a) is an MCNFP.

c Explain why the optimal objective function value for the LP found in part

(a) is the longest path in the project network from node 1 to node 6. Why does this justify our earlier claim that the critical path in a project network is the longest path from the start node to the finish node?