Problem 3 (25 points). The following diagram identifies the activities in a project. The numbers indicate the duration (in days) of each activity. The first activity starts at day zero. (a) What is the total duration of the project? (b) What are the critical activities in the network to keep the project within the schedule without delay? Show the two steps of calculations, the forward and backward passes. Use the activity boxes showing the early start, early finish, late start, late finish, activity ID and duration for each activity. W J N D E N A H W