Answer:The answer to the question "A task with ES = LF and ES = LF is critical" is True.
Explanation:This statement is derived from the definition of the critical path in the Critical Path Method (CPM) of project management. In CPM, the critical path is defined as the sequence of activities that must be completed on time in order for the project to finish on schedule. Therefore, any task that has ES = LF and ES = LF, or in other words any task whose early start and late finish times are equal, is considered critical because any delay in its completion will cause a delay in the entire project's completion. So, the statement is true.