In Problem, suppose that the objective is to minimize the cost of books and that the student total study time is limited to 12,600 hours.

A business student at Nowledge College must complete a total of 65 courses to graduate. The number of business courses must be greater than or equal to 23 the number of non business courses must be greater than or equal to 20. The average business course requires a textbook costing $60 and 120 hours of study. Non business courses require a textbook costing $24 and 200 hours of study. The student has $3,000 to spend on books.

a. Use graphic analysis to determine the combination of courses that minimizes the total cost of books,

b. Identify the slack or surplus variables.