DO NOT use EXCEL, use MATH instead

DO NOT copy the answer from Chegg because it's incorrect and I am posting this question the third time. Please answer both parts because Chegg's guidelines agree to answer both parts of the question.

DO NOT use EXCEL, use MATH instead

DO NOT copy the answer from Chegg because it's incorrect and I am posting this question the third time. Please answer both parts because Chegg's guidelines agree to answer both parts of the question.

Question 3: GH Construction Company is about to begin the construction of a large new home. The company's president is currently planning the schedule for this project. He has identified the major activities (Table below). Activity Description Predecessors B D E F G COAL Find a site Update project details Hire people Procurements Construction Find customers Sell the house Activity Duration (weeks) Optimistic Average Pessimistic 1 2 3 0.5 1 2 1 2 3 2 3 4 5 10 15 1 5 10 1.5 2 2.5 A A CD E, F Part a) Draw the project network and determine the total float for each activity and the critical path in the project network. Part b) Calculate the probability of finishing the project in less than 143 days