Sam and avery are making small and large birdhouses for an upcoming craft show. they will sell the small birdhouses for $10 and the large birdhouses for $15. they want to make as much money as possible. it takes sam 3 hours to build the small houses and 5 hours to build the large ones. he only has 24 hours to work on them. avery only has time to decorate 12 birdhouses of either size before the show. how many small and large birdhouses should they make? how much money will they make?