Wal-Mart, a discount store chain, has completed its new store in Rock Springs, Maryland. The 150,000 square foot store operates seven days per week and requires the following number of full-time employees working each day of the week.

Each employee must work five consecutive days each week and then has two days off.  For example, any employee who works Sunday through Thursday has Friday and Saturday off.  The store currently has a total of 60 employees available to work.  Wal-Mart has developed the following prioritized goals for employee scheduling:

• The store wants to avoid hiring any additional employees.
• The most important days for the store to be fully staffed are Saturday and Sunday.
• The next most important day to be fully staffed is Friday
• The store wants to be fully staffed from Monday through Thursday.

a. Formulate a linear goal programming model to determine the number of employees who should begin their five-day workweek each day of the week in order to achieve the store's objectives.

b.  Determine the solution that will best achieve the company's goals in employee scheduling.  Interpret the solution results including the levels of goal achievement.