Consider the following work breakdown structure: Start Finish Duration (days) Activity Node Node Optimistic Most Likely Pessimistic A 1 B D 123 BUD 1 2 3 2344 2 41 50 59 3 54 60 66 4 58 70 82 4 32 41 44 What is the estimated expected (mean) time for activity D? Consider the following work breakdown structure: Start Finish Activity Node Node Optimistic Duration (days) Most Likely Pessimistic A 1 2 BCD 1 3 23 41 50 59 54 60 66 2 4 58 70 82 3 4 32 41 44 What is the estimated slack time for activity D