4. A construction company planned for a new project and represented the tasks of the project as a graph. The below table belongs to this project showing each task with their three different duration estimates and precedence relationships. ACTIVITY a A 1 B 2 W23 m b IMMEDIATE PREDECESSORS 3 4 C 4 5 6 A D 8 9 10 B E 2 5 8 C, D F 4 5 6 D G 1 2 3 E a. Fill the empty cells in the below table for each activity by developing a network diagram and performing critical path analysis (forward and backward pass): as well as conducting PERT analysis assuming each activity's completion time can be modelled by beta distribution and whole project duration can be modelled by normal distribution. (20 points) G F E D C B b. Calculate the completion time that you can assure with 99% confidence based on the normality assumption and the parameters you have derived above. (20 points) A Activity ES EF LS LF Slack Expected Variance Is Critical Std Dev