Joe offered to sell Harry his car for a specific price and Harry indicated that he needed some time to think about it. Two days later, Joe sold the car to a third party. That afternoon Harry phoned Joe and told Joe that he had decided to accept the offer and that he'd buy the car. Joe told him that it was too late; he had sold it to someone else. Harry said that it was offered to him first, and he insisted that he go through with the contract. Explain the legal liability of the parties.