Nine jobs need to be completed within 8 weeks. The number of weeks required to complete each job is given in the file P08_26.xlsx. For example, job 2 requires 3 weeks. Each week, 160 hours of regular time labor are available. Up to 40 hours of overtime labor can be purchased each week at a cost of $10 per hour. Additional overtime hours cost $20 per hour. a. Determine how to minimize the overtime cost incurred in completing the jobs within 8 weeks. b. The file P08_26.xlsx also lists the due date for each job. For example, job 2 should be completed within 6 weeks. A penalty of $500 is incurred for each day a job is late. Determine how to minimize the sum of overtime and due date penalties.