45. Repeat the questions in Exercise 44 using the order-requirement digraph obtained by erasing all the (directed) edges shown there. How do the schedules you obtain compare with the ones you originally got?
45.
(a) (i) Machine 1: 12, 9, 15, idle from 36 to 50; Machine 2: 7, 10, 13, 20
(ii) Machine 1: 12, 13, 20; Machine 2: 7, 9, 15, 10, idle from 41 to 45
(iii) Machine 1: 20, 12, 9, idle from 41 to 45; Machine 2: 15, 13, 10, 7
(b) None of the schedules found is optimal
(c) The critical path list is T6, T5, T4, T1, T7, T2, T3. This list does not lead to an optimal schedule, but there is a schedule where the completion time is 43, achievable by scheduling the tasks of length 20, 13, and 10 on Machine 1 and tasks of length 24 and 19 on Machine 2.