W Bigwell construction has developed tasks duration and predecessor relationships in the following table for building model houses. The manager has been concerned with the amount of time it took to complete severaljobs, some of the company workers are very unreliable. A list of activities and their optimistic completicm time, the most likely time and the pessimistic completion time {in days] for a new contract are given in the following table. 1' Iecessors Optimistic Most II1|\":er A B C D -3- - -_ 3 Table I. A. Draw the activity network for this new contract {either ADN or ADA}. (4 marks] B. Determine the Expected Time and Variance for each activity. (4 marks] C. Show the activity schedule {ES+ EF. LS. and LF} as well as slack {in table}. (5 math} D. Determine and state the critical path for this project. This M1151 be based on your work in {(3.} and not by inspection. (2 marks] E. 1What are the expected time and the variance of the project? (2 marks] F. What is the probability the project will be I'mished within 20 weeks? {2 Herb} (Taro! B moth