THREE ZERO Please show ALL your work and EXPLAIN your answer. Help with the incomplete question

The estimated times and immediate predecessors for the activities in a project at Howard Umrah's retinal scanning company are given in the following table. Assume that the activity times are independent. Immediate Predecessor(s) Time (weeks) b m Activity A B Time (weeks) a b 7 10 12 5 12 16 Activity C D Immediate Predecessor(s) A B 7 6 10 8 12 14 This exercise contains only parts a, b, c, d, and e. a) Based on the activity time estimates, the expected times and variance for each of the activities are (round your response to two decimal places): Expected Time Activity Variance A 9.83 0.69 B 11.50 3.36 9.93 0.69 D 8.67 1.78 b) The expected completion time of the critical path = 20.17 weeks (round your response to two decimal places). The expected completion time of the path other than the critical path = weeks (round your response to two decimal places)