$3.(20\%)$ You must schedule a project with activities below. Assume the latest finish time is equal to the earliest finish time.

Activity Predecessors Duration $($days$)$

A $-3$

B A $4$

C A $6$

D B $3$

E B $2$

F E $3$

G C$,$ D $2$

H G $4$

I H $4$

a$.$ Construct an Activity on Node representation of the project and perform the forward and backward passes to determine earliest and latest start and finish times.

b$.$ State the activities along the critical path.