In a machine tool workshop four jobs are expected to be processed on four different machines. The jobs are labeled as JB1, JB2, JB3, and JB4, and their corresponding operations processing times on each machine are shown in the following Table Q5(e): Table Q5(c) Job Number Machine P Machine Q Machine R Machine S JB1 58 14 13 48 JB2 35 18 32 JB3 28 15 17 45 JB4 64 16 12 38 10 Estimate the schedule, using the extension of Johnson's rule, the flow shop problem of four jobs through four machines and show them in the Gantt chart