Network Diagrams Simplified

Question
A network consists of the following list. Times are given in weeks. (20 points)

Activity	Preceding	Duration
A		6
B	A	4
C	A	5
D	A	4
E	B	10
F	B	8
G	C,F	3
H	D	3
I	H	8
J	G,I	6
K	E,J	2

a. Draw the network diagram.
b. Which activities form the critical path?
c. How much slack exists at each activities?
d. What is the duration of the critical path?