Patricia Zell, a dollmaker from Olney, Maryland, is interested in the mass marketing and production of a ceramic doll of her own design called Tiny Trisha. The initial investment required for plant and equipment is estimated at $25,000. Labor and material costs are approximately $10 per doll. If the dolls can be sold for $50 each, what volume of demand is necessary for the Tiny Trisha doll to break even?