Determine the critical path, total slacks for each activity and project duration for the network represented by the following table. Discuss the degree of sensitivity embodied by the network.

Activity	Predecessor	Duration (days)
A	--	1
B	A	30
C	A	60
D	A	30
E	D	20
F	B	45
G	C,F	95
H	G	50
I	E	50
J	I	90
K	H,J,L	75
L	C	155
M	K	120
N	M	20