Immediate Predecessor(s) Time (weeks) 6 -- Activity A B 8 A B 10 D Description Site surveying Development of initial design Obtain board approval Establish budget Select architect Finalize design Obtain remaining financing Hire contractor 8 E F G C DE E F,G 6 12 8 H 6 C. a. Draw an activity-on-nodes network for this project. b. Identify the critical path(s) and the duration of this project. The activity times are estimates only. The project planner decides to add variability using minimum (optimistic) durations that for each activity are half the (realistic or most likely) durations given in the table, as well as maximum (pessimistic) durations that are twice the most likely durations. Find the expected duration of the project. d. Estimate the probability that the project can be completed within 65 weeks (i.e., fifteen months). (Compute both optimistic and pessimistic probability estimates.) For the rest of the problem, use the most likely times only. e. To reduce the project duration, each activity can be reduced from the most likely time to the optimistic time at a cost inferred from the table below. (All costs are in $1,000s, and the crashing cost is proportional to the amount of time crashed.) Determine the least-cost way to reduce the project duration to 52 weeks. A B C D E F G H Task Normal cost Crashed cost 4 15 5 12 10 21 20 40 20 120 6 12 20 30 6 30 f. In addition to the indicated activity costs, there are overhead costs of $6,000 per week for the entire project. Taking into account both the costs of crashing the activities and the overhead costs, find the activity durations that will minimize the total project cost