Megah Holdings is a company that installs piping and hold drains in residential construction. This company has been concemed with the amount of time that it takes to complete piping jobs. A list of activities of optimistic, most likely, and pessimistic times in days are given in the table below. Activity Immediate Predecessors Optimistic (a) Most likely (m) Pessimistic (b) A LC! 2 1 6 3 4 :5 I'I'I B C D E F G H | J 'L 'L "NI \"Em-n U'I-lh-DJ a) Calculate the expected completion time and variance for each activity (2 decimal). (4 marks) b} Determine the project completion time and the critical path for installing electrical winng and equipment in residential houses. (7" marks) c)- What is lhe probability that the project will be finished ve days before the expected completion time? (4 marks)