Answer:
The above statement is true.
Step-by-step explanation:
In the English language, the word slack generally means to reduce speed or to become negligent towards a particular project or action. It refers to something weak, low, slow or careless. I means that something s not happening in the proper way that it should.
Hence the statement 'lack is the amount of time an activity can be delayed without delaying the entire project. ' is true.