Sam is in his final year of college and is trying to schedule his courses for the year. He has narrowed his search to 16 courses, each of which is offered in at least one time slot (out of a possible five time slots) in each semester. The file P06_89.xlsx lists the courses and when they are offered. For example, course C1 is offered in time slots T4 and T5 during semester S1 and in time slot T3 in semester S2. The course also lists the values Sam attaches to the various course/time slot/semester combinations (on a 1 to 10 scale). Assuming that Sam must take exactly five courses each semester, find the combination that maximizes the total value of the courses he takes. Of course, he can’t take the same course more than once, and he can’t take more than one course at the same time.