Study the activity list and its network diagram. Calculate the early start, early finish, late start and late finish of activity $C.$

a$.ES=2,EF=5,LS=6,LF=10$

b$.ES=5,EF=3,LS=6,LF=8$

c$.ES=3,EF=5,LS=8,LF=10$

d$.ES=2,EF=5,LS=6,LF=6$