Consider the Following Work Breakdown Structure What Is the Estimated Standard Deviation in the Time for (Days)

Multiple Choice

Consider the following work breakdown structure: $$\begin{array}{r}\text { Duration Estimates (Days) }\quad\quad\quad\\\begin{array} { l c c c c } \text { Activity } & \text { Precedes } & \text { Optimistic } & \text { Most Likely } & \text { Pessimistic } \\\hline \text { Start } & \text { U, V } & - & - & - \\\text { U } & \text { W } & 35 & 50 & 65 \\\text { V } & \text { W, X } & 28 & 40 & 52 \\\text { W } & \text { Z } & 26 & 35 & 44 \\\text { X } & \text { Y } & 28 & 40 & 52 \\\text { Y } & \text { Z } & 26 & 29 & 38 \\\text { Z } & \text { End } & 36 & 60 & 84\end{array}\end{array}$$ What is the estimated standard deviation in the time for activity Z?

A) 3 days
B) 2 days
C) 4 days
D) 8 days
E) 5 days