$($B$)$ A small project consists of seven activities with the following details.

$\backslash$table$[[$Activity$,$DURATION, WEEKS,$\backslash$table$[[$Immediate$],[$Predecessor$]]],[\backslash$table$[[$Most$],[$likely$]],$Optimistic,Pessimistic$],[$A$,4,2,8,$A$],[$B$,7,3,15,$A$],[$C$,4,4,23,$B$,$ C$],[$D$,11,5,16,$B$],[$E$,8,4,15,$D$,$ E$],[$F$,6,3,5,$D$],[$G$,5,5,,]]$

$($i$)$ Draw Network Diagram, find critical path, the expected completion time.

$($ii$)$ What project duration will have $95\%$ confidence of completion? Take $Z=1\mathrm{.}64\mathrm{.}10$