....15.22 The following set of seven jobs is to be processed through two work centers at George Heinrich's printing com- pany. The sequence is first printing, then binding. Processing time at each of the work centers is shown in the following table: JOB T PRINTING (HOURS) BINDING (HOURS) 15 3 > > W X > U 7 9 4 10 7 6 10 9 Y 4 5 Z 7 8 a) What is the optimal sequence for these jobs to be scheduled? b) Chart these jobs through the two work centers. c) What is the total length of time of this optimal solution? d) What is the idle time in the binding shop, given the optimal solution?