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:

$\backslash$table$[[$Activity$,$Time $($weeks$),$Immediate Predecessor$($s$),$Activity,Time $($weeks$)],[$A$,7,-,$Immediate Predecessor$($s$),,],[$B$,7,-,$F$,5,$B$],[$C$,3,$A$,$G$,7,$B$],[$D$,3,$A$,$H$,6,$C$,$ E$]]$

Dave's earliest start $($ES$)$ and earliest finish $($EF$)$ are:

$\backslash$table$[[$Activity$,$ES$,$EF$],[$A$,,7],[$B$,0,],[$C$,,10],[$D$,7,],[$E$,,12],[$F$,7,],[$G$,,21],[$H$,-,20]]$

Dave's latest start $($LS$)$ and latest finish $($LF$)$ are:

$\backslash$table$[[$Activity$,$LS$,$LF$],[$H$,15,],[$G$,12,-],[$F$,8,-],[$E$,7,-],[$D$,12,],[$C$,9,-],[$B$,0,],[$A$,2,]]$

The slack times are:

$\backslash$table$[[$Activity$,$Slack$],[$A$,-],[$B$,],[$C$,],[$D$,-],[$E$,-],[$F$,],[$G$,],[$H$,]]$

The total project completion time for Dave $=$ weeks.