Need help for c, d and e.

A small software development project at Krishna Dhir's firm has five major activities. The times (in days) are estimated and provided in the table below: Immediate Predecessor m b Activity a 2 8 B D E A B 3 4 2 3 5 6 7 5 3 9 10 14 3 a) The expected completion time for this project is 15 days (enter your response as a whole number). b) The project variance of completion time is 2 days (enter your response as a whole number). C) The probability that this projectbe can be completed in 17 days or less is (keep two decimal places). d) The probability that it will take more than 17 days to complete this projectbe is (keep two decimal places). e) The due date that yields a 98% chance of completion is days (keep two decimal places)