Building a backyard swimming pool consists of nine major activities. The activities, their immediate predecessors, and times are shown. (I have calculated for you the expected times and the variances.)

Activity Immediate Optimistic Most Pessimistic Expected Var.

Predecessor Probable Times

A - 3 5 7 5 .44

B - 2 4 6 4 .44

C A,B 5 6 7 6 .11

D A,B 8 9 10 9 .11

E B 2 4 6 4 .44

F C 1 2 3 2 .11

G D 5 7 9 7 .44

H D,F 5 8 11 8 1.00

I E,G,H 3 4 5 4 .11

You do not have to submit the diagram. Show work on all questions. What are the activities on the critical path?

What is the probability that the project can be completed in 28 days?