If the values Earliest time and Latest time of an event are not equal then such events are referred to as: A. critical B. optimum C. non-critical D. All of the above E. None of the above

The correct answer is: C. non-critical

An event is said to be critical if its earliest time and latest time are equal. This means that the event must occur on time, or else the entire project will be delayed. Non-critical events, on the other hand, have some flexibility in their timing. They can occur earlier or later than their earliest time, as long as they occur before their latest time.

Here is a brief explanation of each option:

• Critical: A critical event is an event that must occur on time, or else the entire project will be delayed. This is because the earliest time and latest time for a critical event are equal. If the event occurs later than its latest time, then the project will be delayed by the amount of time that the event was late.
• Optimum: An optimum event is an event that occurs at its earliest time. This is because there is no benefit to delaying an optimum event, as it will not affect the overall project schedule.
• Non-critical: A non-critical event is an event that has some flexibility in its timing. It can occur earlier or later than its earliest time, as long as it occurs before its latest time. Non-critical events are not as important as critical events, and they can be delayed without affecting the overall project schedule.
• All of the above: This option is incorrect because it includes both critical and non-critical events. Critical events are not the same as non-critical events, and they should not be grouped together.
• None of the above: This option is also incorrect because it does not include any of the possible answers. The correct answer is “C. non-critical.”