Consider a project having the following seven activities: $(15$ pts$)$

$($a$)$ What is the expected time for each activity?

$($b$)$ What is the expected project completion time?

$($c$)$ What is the critical path?

$($d$)$ What is the variance for each activity?

$($e$)$ What is the probability that the project will be completed in less than $24$ weeks?