Dave Fletcher was able to determine the activity times for constructing his laser scanning machine. Fletcher would like to determine ES, EF, LS, LF, and slack for each activity. The total project completion time and the critical path should also be determined. Here are the activity times: Activity Time (weeks) Immediate Predecessor(s) Activity Time (weeks) Immediate Predecessor(s) A 6 minus E 4 B B 7 minus F 6 B C 3 A G 10 C, E D 2 A H 7 D , F Dave's earliest start (ES) and earliest finish (EF) are: Activity ES EF A 0 6 B 0 7 C 6 9 D 6 8 E 7 11 F 7 13 G 11 21 H 13 20