On May 1, Newtown Motors, a used-car dealer, wrote a letter to O'Reilly, which stated, "We have a 1969 Pontiac Firebird in mint condition that we will sell you for $12,500 at any time before June 1. [Signed] Newtown Motors." By May 15, having heard nothing from O'Reilly, Newtown Motors sold the Firebird to another party. On May 25, O'Reilly told Newtown Motors that he accepted the offer and tendered $12,500. When Newtown Motors told O'Reilly it had sold the car to another party, O'Reilly claimed Newtown Motors had breached their contract. Is Newtown Motors in breach? Explain.