Activity Predecessors Duration Weekly (Weeks) Cost Total A 9 $ 2,000 $ 18,000 B A 3 $ 4,000 $ 12,000 A 6 $ 4,000 $ 24,000 D B 7 $ 5,000 $30,000 E 8 $ 5,000 $ 40,000 F F 7 $ 4,000 $ 28,000 G DE 6 $ 3,500 $ 21,000 a. Compute the ES and LS for the project. What is the critical path? b. Construct the time-based network Gantt chart for the project using early start times. c. What is the weekly cost at the end of week 11, week 18