a m b D 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. Time (weeks) Immediate Time (weeks) Immediate Activity a m b Predecessor(s) Activity Predecessor(s) 9 10 11 7 10 11 A B 6 12 17 5 10 11 B This exercise contains only parts a, b, c, and a 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 Activity Time Variance B b) The expected completion time of the project - weeks (round your response to wo decimal places) c) The project variance of completion time weeks (round your response to two decimal places). d) If the time to complete the project is normally distributed, then the probability that the project will be finished in 23 weeks or less - center as a probability and round your response to two decimal places) Enter your answer in the edit fields and then click Check