Mike is an artist and sells his work at various art fairs. He only paints fish and squirrels. Fish paintings take him 12 hours to paint and another 6 hours to build a frame for it. Squirrels paintings take him 6 hours to paint and 6 hours to build a frame. Mike can only paint for 36 hours a week and build frames for 24 hours a week.
If a fish painting sells for $50 and each squirrel painting sells for $35, how many of each painting should he make to maximize earnings?