Linear Programming : Forumulation

Product Mix

A carpenter specializes in making bookshelves and desks. Each bookshelf earns a profit of $36, while each desk earns a profit of $40. A bookshelf requires 48 ft. of wood and takes 16 hrs. to make, while a desk requires 40 ft. of wood and takes 20 hrs. to make. The carpenter has 480 ft. of wood available, and is willing to spend up to 200 hrs. to make the bookshelves and desks. How many bookshelves and desks should be made to maximize total profit?

Please just set up the problem showing the variables and constraints etc.