Activity	Immediate Predecessors	Expected time (a+4m+b)/6	Variance
A		(6 + 4(8) + 9)/6 = 7.83	.25
B		(9 + 4(12) + 15)/6 = 12.00	1.00
C	A, B	(4 + 4(6) + 11)/6 = 6.50	1.36
D	B	(3 + 4(4.5) + 6)/6 = 4.50	.25
E	A	(1 + 4(2) + 3)/6 = 2.00	.11
F	C	(1 + 4(3) + 5)/6 = 3.00	.44
G	E, F	(5 + 4(6) + 10)/6 = 6.50	.69
H	D, F	(2 + 4(3) + 4)/6 = 3.00	.11
I	G, H	(1 + 4(1) + 1)/6 = 1.00	.00
J	I	(2 + 4(3) + 7)/6 = 3.50	.60

1) draw the activity network for the problem.

2) Determine the activity schedule (ES, EF, LS, and LF) as well as slack.