We have a flow shop problem with $2$ machines and $5$ jobs. The table below

provides the processing time for each job on each machine.

Apply Johnson's algorithm to determine the schedule that minimizes makes

span. At each step of the method, you need to provide the set of unscheduled

jobs, the unscheduled job with the smallest processing time on machine $1,$

the unscheduled job with the smallest processing time on machine $2,$ and the

job you will schedule.