A used car dealership can hire both college graduates and non-college graduates. The average number of cars it sells per hour is equal to q = 10 - 10*exp(-0.013c - 0.010n - 1.07), where q is the number of cars sold, c is the number of college graduates working during one hour, and n is the number of non-college graduates working during one hour. The dealership pays college graduates $20/hour and non-college graduates $18/hour. The dealership wishes to maximize its average profit during an hour. We assume that each car is sold for $27,000, and the variable cost (without considering the cost of labor) is $26,000 per car. If the dealership employs n = 5 non-college graduates each hour, how many college graduates should the dealership employ during one hour?