$\backslash$table$[[,,,,],[,\backslash$table$[[$Start$],[$Activity$],[$Node$]],\backslash$table$[[$Finish$],[$Node$]],$Duration Estimate $($Days$)],[$Optimistic$,$Most Likely,Pessimistic,,,$],[$A$,1,2,9,15,21],[$B$,1,3,13,21,23],[$C$,2,4,6,9,18],[$D$,2,5,23,35,47],[$E$,3,5,19,26,27],[$F$,4,6,23,29,41],[$G$,5,6,14,20,26],[$H$,6,7,2,5,8],[,,,,,]]$

What is the estimated expected $($mean$)$ time $($in weeks$)$ for project completion?

$35$

$75$

$115$

$170$