Answer this question. Several answers can be correct.

In project management the following holds:

$1)$ CPM assumes fixed deterministic activity times

$2)$ Critical path represent a series of activities that run through the whole process and the sum of their times equals the total project time

$3)$ Earliest start generally represents the latest time at which an activity needs to start to prevent the delays in the project as a whole.

$4)$ Using PERT method we can derive the probability that the project will be finished on time

$5)$ Critical activities are activities with largest slack time