PLEASE SOLVE USING EXCEL SOLVER $($SHOW FUNCTIONS$)$ Midwest Parts Supply $($MPS$)$ is a fabricator of small steel parts that are sold as components to manufacturers of electronic appliances and medical equipment. In the MPS fabrication department, steel sheets are subjected to a series of three main operations: cutting, trimming, and polishing. The operations must be completed in that order for every sheet.

Each machine processes the jobs in the same order, so it is sufficient to specify a single job sequence in order to describe a schedule. No machine can process more than one job at a time. Ten jobs have just been released into the system, and the production manager is interested in minimizing the time it takes to complete the entire schedule, usually referred to as the schedule makespan. Table $4$ shows the hours required for each operation.

a$.$ What sequence achieves the minimum makespan?

b$.$ How long does that minimum makespan take to complete?