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A project with time uncertainty has work breakdown structure, precedence relationships, and activity times as follows. Assume that activities are started as early as possible, i.e. no delays. You need to show project networks, steps, and results in answering the following questions. (a)[2] What is the shortest project completion time among the three possible scenarios? (b) [2] What is the longest project completion time among the three possible scenarios? (c) [1] What is the expected project completion time? (A weighted average among the three scenarios with probabilities specified in the table)