Question $5$

The table below lists three time estimates and the immediate predecessor$($s$)$ for each activity in a construction project that is to be

scheduled using PERT. The three time estimates $($in weeks$)$ are in the order: optimistic time, most likely time, and pessimistic time.

The total variance of the critical path is equal to

$2\mathrm{.}36$

$4\mathrm{.}39$

$1\mathrm{.}54$

$3\mathrm{.}82$