Activity duration estimates indicate: a) When an activity is likely to finish. b) How many work periods an activity is expected to last. c) How many hours a resource will work on an activity. d) When an activity is likely to start. A project plan results in a project schedule that is too long. If the project network diagram cannot change but you have extra personnel resources, what should you do? a) Level the resources b) Perform a resource analysis c) Fast track the project d) Crash the project