A PERT problem is detailed in the table below. Times are given in weeks.

Activity	Preceding	Optimistic Time	Probable Time/ Most likely time	Pessimistic Time
A	--	7	9	14
B	A	2	2	8
C	A	8	12	16
D	A	3	5	10
E	B	4	6	8
F	B	6	8	10
G	C, F	2	3	4
H	D	2	2	8
I	H	6	8	16
J	G, I	4	6	14
K	E, J	2	2	5

1. Calculate the expected time and ES, EF, LF, and LS of each activity.
2. Draw diagram network for this project.
3. What are the project variance and the project standard deviation?
4. What is the estimated completion time?
5. What is the probability of completion of the project after week 40?