A computer$-$system installation project consists of eight activities. The immediate

predecessors and activity times in weeks are as follows:

a$.$ Draw the network for this project.

b$.$ What are the critical$-$path activities?

c$.$ What is the project$-$completion time?

d$.$ As a project manager, where would you focus your attention given your

analysis?

McGee Carpet and Trim installs carpet in commercial offices. Andrea McGee has been very

concerned with the amount of time it took to complete several recent jobs. Some of her

workers are very unreliable. A list of activities and their optimistic completion time, the most

likely completion time, and the pessimistic completion time $($all in days$)$ for a new contract are

given in the following table:

a$)$ Determine the expected completion time and variance for each activity.

b$)$ Determine the total project completion time and the critical path for the project.

d$)$ What is the probability that McGee Carpet and Trim will finish the project in $40$ days or less?