Q$4.(15$ points$)$

Activity Preceding Activities Hours

a $-7$

b $-9$

c a$,$b $7$

d a$,$c $14$

e a $3$

f c$,$d $9$

g c$,$e$,$f $11$

h c $11$

i b$,$c $4$

j h$,$i $5$

k g$,$j $11$

l k $31$

m k$,$l $12$

n m $9$

Based on the list of activities and their requirements:

a$)$ Create a network diagram.

b$)$ Determine the Early Start $($ES$),$ Late Start $($LS$),$ Early Finish $($EF$),$ and Late Finish $($LF$)$ for each activity.

c$)$ Identify the critical path.