7. A network for a small project is shown below with activity duration and required number of laborers. During the first 10 days of the project, the contractor has a maximum of four laborers. Afterwards, a subcontractor will be employed to relieve the work force.

A d=1, r=3 J

5,3

a. Use the early late-start rule (ELS) to resolve any resource conflicts in the first 10 days and calculate the consequent project extension.

b. Briefly describe a suitable strategy for smoothing the labor resource used, assuming the contractor has no resource constraints.