1. Given the network plan that follows, compute the early, late, and slack activity times; determine the planned project duration; and identify the critical path.

Id	Description	Predecessor	Time
A	External Specifications	None	3
B	Review Design Features	A	15
C	Document New Features	A	5
D	Write Software	A	60
E	Program and Test	D	6
F	Edit and Publish Notes	B	40
G	Review Manual	E	10
H	Alpha Site	F	7
I	Print Manual and Beta Site	G	6
J	Manufacture and release	H, I	12