A project consists of seven activities. The following table shows the estimated time of the activities and the precedence relations.

$\backslash$table$[[$Activity$,\backslash$table$[[$Estimated$],[$durations $($days$)]],\backslash$table$[[$Immediate$],[$predecessor$]]],[$A$,9,],[$B$,10,$A$],[$C$,5,$A$],[$D$,3,$B$,$ C$],[$E$,6,$B$,$ C$],[$F$,3,$D$,$ E$],[$G$,4,]]$

What is the EF for activity F$?$