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Table Q(b) summarizes the probabilistic time estimated for activity A to H. Determine: (i) the expected time, variance and standard deviation for each activity, (ii) the probability the project will not be able to complete in 20 days and, (iii) the completion time with 90% chance of success. Table Q(b): Probabilistic Time Estimated (Days) Activity Predecessors Optimistic Most likely Pessimistic Time (ta) Time (tm) Time (tb) A 1 2 3 B 0 1 3 A,B 1 3 4 D 3 4 5 E D 4 5 6 F D 3 4 6 G F 3 5 6 G 1 2 3 AU Q H