Please help me solve this question

The following table represents the set of activities required to complete a project, along with their time estimates for PERT Calculations. a. Using the data in the table, calculate the expected time (ET) and variance for each activity Job time (ET) Predecessor number Job(s) amb expected variance A 3 4 5 B A 1 2 3 B (2 3 4 D B 3 6 9 E CD 4512 F DE 14 7 b. [Sketch the network diagram for the project on a sheet of paper. YOU DO NOT HAVE TO SUBMIT THE SKETCH AS PART OF YOUR ANSWER), c. Ust each unique path through the network. For example, "A B C would indicate a path consisting of activity A, followed by activity B, which is followed by activity C d. Indicate the critical path. You can do this by inspecting the paths - you do not have to calculate ES, EF, LS, LF) What is the expected completion time for the project? e. What is the probability that the project will be completed in 25 days or less? What is the probability that the project will take more than 25 days to complete