Sartorial, Inc., a new business enterprise about to commence the manufacture of clothing, entered into a written agreement to purchase all of its monthly requirements of a certain elasticized fabric for a period of three years from the Stretch Company at a specified unit price and agreed delivery and payment terms. The agreement also provided: 1. The parties covenant not to assign this contract. 2. Payments coming due hereunder for the first two months shall be made directly by Sartorial to Virginia Wear and Son, Inc., a creditor of Stretch. Stretch promptly made an "assignment of the contract" to Finance Company as security for a $100,000 loan. Sartorial subsequently ordered, took delivery of, and paid Stretch the agreed price ($5,000) for Sartorial's requirement of the fabric for the first month of its operation.Assume for this question only that the assignment from Stretch to Finance Company was effective, and that Sartorial was unaware of the assignment when it paid Stretch the $5,000. Which of the following is correct?
Sartorial is liable to Finance Company for $5,000.  Stretch is liable to Finance Company for $5,000.  Sartorial and Stretch are each liable to Finance Company for $2,500.  Neither Sartorial nor Stretch is liable to Finance Company for any amount