McGee Carpet and Trim installs carpets in commercial offices. Andrea McGee has been very worried with amount of time it took to finish many recent jobs. Some of her workers are very unreliable. List of activities and their optimistic completion time, most probable completion time, and pessimistic completion time (all in days) for new contract are given in given table. Following are activities which are required to install carpets in offices: Activity 1 (Measure office room dimensions), Activity 2 (Estimate cost), Activity 3 (Material Requisition), Activity 4 (Workforce Requisition), Activity 5 (Special Tool Requisition), Activity 6 (Installation), Activity 7 (Inspection and customer acceptance).