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Optimistic Time (t) Most Likely Time (tm) Pessimistic Time (tp) Activity 8 13 b. k 10 15 13 12 15 15 14 17 20 Compute the mean path duration and the path variance. 16. A project has the following activities, precedence relationships, and time estimates in days: Immediate Predecessor Activity Activities a ba Optimistic Time (t) Time (t) Most Likely Time (tm) Time (t...) Pessimistic Time (to) 4 4 5 8 7 10 7 4 6 8 of the oro 6 ef A k hij a. Compute the duration (expected time) and variances for each activity. b. Draw a PERT network. c. Compute the EF, LF, and slack for each activity. Write the values on the PERTI network d. Compute the ES and LS for all activities. Display the ES, EF, LF, and slack values in a table. e. What is the critical path? f. What is the probability that the project will take longer than 38 days