What is the slack for each activity

Question

Problem:

Consider a project having the following six activities:

                          Immediate
Activity              Predecessors           Time (weeks)
A                       none                              7
B                       none                              3
C                         A                                 5
D                       A, B                               6
E                        C, D                              4
F                          D                                3

1. Draw the project network and list the earliest start (ES), earliest finish (EF), latest start (LS) and latest finish (LF) for each task.

2. List the tasks on the critical path

3. What is the expected project duration in weeks?

4. What is the slack for each activity?

A:      B:      C:     D:      E:      F: