4. Use the information, A (the optimistic time), M (the most likely time), and B (the pessimistic time), in Table 1 to do PERT calculations and to solve the problem. (15 points) (a) Draw an activity-on-the-arrow network model and find the critical path. Calculate the estimated completion time of the project and the standard deviation for the project duration. (b) As the project manager, how would you respond to your boss if s/he said to you that your team needs to complete this project within 15 months? No. Task Predecessors B A (months) M (months) (months) 1 A 2 3 5 2 B 1 2 3 3 A 2 4 6 4 D A, B 1 3 4 5 E A, B 2 5 6 6 F 3 4 5 7 G D, E 1 2 4 Table 1