The home office billing department of a chain stores prepares monthly inventory reports

A)     The home office billing department of a chain stores prepares monthly inventory reports for use by the stores purchasing agents. Given the following information, use the critical path method to determine:
1) How long the total process will take
2) Which jobs can be delayed without delaying the early start of any subsequent activity
Job & Description Immediate Predecessors Time (Hours)
A Start - - 0
B Get computer printouts of customers purchases A 10
C Get stock records for the month A 20
D Reconcile purchase printouts and stock records B,c 30
E Total stock records by department. B,c 20
F Determine reorder qtities for coming period E 40
G Prepare stock reports for purchasing agents D,f 20
h Finish g 0