2. A small software development project has 9 major activities. The times are estimated and provided in the network below. [15 points) 3 G A 4 c 5 6 F 7 B 3 NM (a) Using the method of ES, EF, LS, and LF, determine the project completion time? (b) Find the critical path(s). () State the non-critical activities. S-LES (a) Explain what it means if an activity has a slack of zero (give an example). (c) Explain what it means if an activity has a slack of non- zero (give an example)