Jane and Dick entered into an oral agreement for Jane to sell Dick a parcel of real property. Their oral agreement included a description of the property to be sold, the price of the property, and the date of the closing of the transaction. An unsigned written contract was prepared by Jane's attorney and sent to Dick by messenger together with an enclosed addressed Federal Express return envelope. Dick signed the agreement but lost the Federal Express return envelope. Dick sent the signed contract back to Jane through regular mail for her signature. Before Jane received the contract, Mr. Spot made Jane an offer for the property including an increase in the purchase price of $10,000 more than Dick had offered her. Jane immediately called Dick to cancel the deal. Dick sued Jane for specific performance. What are Jane's two best arguments in defense against Dick's claim for breach of contract?