Slack is the calculated time span within which the event must occur: A. TRUE B. FALSE C. cannot be said D. All of the above E. None of the above

The correct answer is: B. FALSE

Slack is the amount of time between the earliest and latest start or finish times of an activity. It is calculated by subtracting the earliest start time from the latest start time, or the earliest finish time from the latest finish time.

The earliest start time of an activity is the earliest time at which the activity can start, given the start times of the activities that must precede it. The latest start time of an activity is the latest time at which the activity can start without delaying the project. The earliest finish time of an activity is the earliest time at which the activity can finish, given the start and finish times of the activities that must follow it. The latest finish time of an activity is the latest time at which the activity can finish without delaying the project.

Slack is important because it indicates how much flexibility there is in the schedule of an activity. If an activity has a lot of slack, then it can be delayed without causing any problems for the project. However, if an activity has very little slack, then it is important to make sure that it starts and finishes on time.

In conclusion, slack is not the calculated time span within which the event must occur. It is the amount of time between the earliest and latest start or finish times of an activity.