What do you mean by Critical Path Method? The three time estimate $t_0,t_m,$ and $t_0$ of each activities of a project are given below:

$)=(20$

$\backslash$table$[[$Activity$,t_o($days$),t_m($days$),t_p($days$)],[1-2,2,5,14],[1-3,3,12,21],[2-4,5,14,17],[3-4,2,5,8],[4-5,1,4,7],[3-5,6,15,30]]$

$($a$)$ Draw the network diagram

$($b$)$ Find the expected duration and variance of each activities.

$($c$)$ Calculate the early and late occurrence times for each event

$($d$)$ Determine the expected duration