Consider the following network for conducting a two$-$week $(10$ working days$)$ computer training class:

$($a$)$ Construct a crchedule showing:

ESs for all activities

LSs for all activities

Slacks for all activities

Critical path

$($b$)$ Given the following.

$\backslash$table$[[,\backslash$table$[[$Crash$],[$Time$],[$Activitys$)]],\backslash$table$[[$Crashed$],[$Cost$],[($total$)]],\backslash$table$[[$Normal$],[$Time$],[($days$)]],\backslash$table$[[$Normal$],[$Cost$]]],[$A: Obtain,$4,$$$800,7,$$$500$