An artist can make two kinds of ornaments, free standing or hanging. He can make at most 50 ornaments each week, and the greatest number of hours he can work in a week is 70. It takes 2 hours to make a free standing ornament and 1 hour to make a hanging ornament. His profit is $9 for each free standing ornament and $12 for each hanging ornament. How many of each type ornament should he make to maximize his profit