Question 24 Which of the following statements regarding PERT times is true? Select one: a. The optimistic time estimate is an estimate of the minimum time an activity will require b. Most likely time estimate is an estimate of the maximum time an activity will require c. The optimistic time estimate is an estimate of the maximum time an activity will require d. Pessimistic time estimate is an estimate of the minimum time an activity will require e. The probable time estimate is calculated as t = (a + 4m + b).