A project manager, dealing with a project with uncertain activity times, identified the following activity information for this project. Activity Immediate Predecessor ABCDEFGHI I A - C B. D E B. D G F. H Optimistic time Most probable time Pessimistic time (Weeks) 2.0 2.5 2.0 2.0 1.0 2.0 3.5 4.0 2.0 (Weeks) 1.5 2.0 1.0 1.5 2 0.5 1.0 3.0 3.0 1.5. (Weeks) 2.5 6.0 3.0 2.5 1.5 3.0 7.0 5.0 2.5 a) Draw the project network. (1 marks) b) Prepare the activity schedule? (2 mark) c) What are the critical activities, what is the expected project completion time, and the variance on critical path? (3 mark)