On your software development project, accurately estimating the durations of activities is important. You suggest to management that PERT estimates be completed for each activity. You give them the following example. Your programmer estimates that 100 hours will most likely be required to complete the work.

However, an optimistic estimate is 80 hours, whereas a pessimistic estimate is 150 hours. The PERT estimate is:

a. 100 hours

b. 105 hours

c. 110 hours

d. 150 hours