Key information on a product new release project is captured in the hereunder table, including

activities, predecessors, expected durations and variances $($in days$).$

$1)$ What is the critical path of the project? Please include the project network, either in

Microsoft Project, or manually if neatly drawn. In either case, make sure you clearly

show the critical path.

$2)$ What is the probability of completing the project in $20$ days? $30$ days?