Hint: p$(0<$ z $<1\mathrm{.}645)=0\mathrm{.}45$

Activity

Immediate

Predecessors

Completion Time $($Weeks$)$

Optimistic

Most Likely

Pessimistic

A

N$/$A

$1$

$2$

$3$

B

A

$2$

$4$

$6$

C

A

$2$

$5$

$8$

D

A

$1$

$1$

$1$

E

B$,$ C

$2$

$3$

$4$

F

D

$1$

$2$

$3$

What is the $90\%$ confidence interval of the total project completion time?

Group of answer choices

$6$~$13$

$8$~$12$

$7$~$10$

$5$~$8$