Consider the following:

$\backslash$table$[[$Activity$,\backslash$table$[[$Normal$],[$time$]],$Crash time,Normal cost,Crash cost,Predecessor$],[$A$,4,3,2200,2600,],[$B$,2,1,2400,2800,],[$C$,3,3,500,500,],[$D$,8,4,2200,2600,$A$],[$E$,6,3,600,1200,$B$],[$F$,3,2,3600,4200,$C$],[$G$,4,2,1200,2000,D,E$