1. (30 pts.) Consider the project whose activity precedence and duration estimates data are provided in the following table. Suppose that a pessimistic duration estimate refers to a value that ought to be exceeded only once in 100 trials, and that an optimistic duration estimate refers to a value that ought to be bettered once in 100 trials. Answer the following questions using the included probability table when needed. a. Determine expected duration and standard deviation of all activities, the expected duration of the project and its standard deviation according to PERT. b. Determine the probability of completing the project in at most 25 days according to PERT. c. Calculate the probability of the critical path activities being completed and the project not being completed in 25 days. What does this probability say about the project? d. The estimators state that their pessimistic and optimistic duration estimates refer to once in 20 trials. What would change? Why? ID Predecessor None A B Duration Estimates (in days) Optimistic Most Likely Pessimistic 10 10 10 2 5 8 2 2 2 2 2 26 3 6 15 A A D A E F G 5 0 20 0 B,C D E,F