NOW, TRY ONE ON YOUR OWN...

ACTIVITIES PREDECESSOR DURATION

$\backslash$table$[[$A$,$NONE,$2],[$B$,$A$,2],[$C$,$A$,6],[$D$,$A$,4],[$E$,$A$,3],[$F$,$B$,7],[$G$,$C$,$ F$,1],[H,$C$,$ F$,5],[$I$,$A$,5],[$J$,$D$,$ E$,8]]$