Consider the following work breakdown structure:
duration estimates days
activity precedes optimistic most likely pessimistic
start u, v - - -
u w 35 50 65
v w, x 28 40 52
w z 26 35 44
x y 28 40 52
y z 26 29 38
z end 36 60 84
what is the estimated expected (mean) time for project completion?
a. 135 days
b. 145 days
c. 170 days 1
d. 80 days
e. 255 days