Pik-Fast, a chain of convenience stores, is planning to open a new store. The activities required, their immediate predecessors, and the optimistic, most likely, and pessimistic estimates of their times (in days) are provided below.

Activity	Description	Immediate Predecessors	Optimistic Time (days)	Most Likely Time (days)	Pessimistic Time (days)	TE	ES	EF	LF	LS	Slack	Standard Dev	Variance
A	Select manager	--	10	12	20	13					0	1.67
B	Select site	--	8	15	22	15					0	2.33
C	Hire workers	A	17	21	31	22					0	2.33
D	Basic training	C	3	4	5	4					0	0.33
E	Secure permits	B	12	18	30	19					0	3.00
F	Construct building	E	26	30	40	31					0	2.33
G	Purchase equipment	--	30	45	60	45					0	5.00
H	Install equipment	F,G	4	6	8	6					0	0.67
I	Advertise opening	B	15	55	89	54					0	12.33
J	Final training	D,H	2	3	4	3					0	0.33
K	Stock store	H,I	4	6	8	6					0	0.67
L	Open store	J,K	1	1	1	1					0	0.00

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b) Identify the critical path and projected project completion time using the expected completion times.

c) Calculate the expected slack times for any two paths not including the critical path. For the path slack time, compute this compared to the critical path and that also considers the slack time for each activity on that path.

d) Find the probability that the critical path will be completed within 80 working days.