Mary Frost, a new entrepreneur, is considering selling Do-All Software, a home-office software package, at a computer convention in Chicago. Mary can purchase this software from a computer software wholesaler at $120 per package, with the privilege of returning all unsold packages and receiving a full $120 refund per package. The packages would be sold for $200 each. She would pay $2,000 to Computer Conventions, Inc., for the booth-rental for the convention. Assume there are no other costs.