A travel agency offers two types of vacation packages: beach vacations for $550 per person, and mountain vacations for $750 per person. It costs $480 per person to advertise beach vacations, and it costs $680 per person to advertise mountain vacations. The agency has an advertising budget of $10,200 and can accommodate a maximum of 20 people. The agency is trying to figure out how to maximize revenue. What are our two constraints for this problem