Given the following network with activities and times estimated in days,

$264.$png

Activity

Optimistic

Most

Probable

Pessimistic

A

$2$

$5$

$6$

B

$1$

$3$

$7$

C

$6$

$7$

$10$

D

$5$

$12$

$14$

E

$3$

$4$

$5$

F

$8$

$9$

$12$

G

$4$

$6$

$8$

H

$3$

$6$

$8$

I

$5$

$7$

$12$

J

$12$

$13$

$14$

K

$1$

$3$

$4$

$$

a$.$

What are the critical path activities?

b$.$

What is the expected time to complete the project?

c$.$

What is the probability the project will take more than $28$ days to complete?