For several weeks Mater, a wealthy, unemployed widow, and Nirvana Motors, Inc., negotiated unsuccessfully over the purchase price of a new Mark XX Rolls-Royce sedan, which, as Nirvana knew, Mater wanted her son Dilbert to have as a wedding gift. On April 27, Nirvana sent Mater a signed, dated memo saying, "If we can arrive at the same price within the next week, do we have a deal?" Mater wrote "Yes" and her signature at the bottom of this memo and delivered it back to Nirvana on April 29. On May 1, Mater wrote Nirvana a signed letter offering to buy "one new Mark XX Rolls-Royce sedan, with all available equipment, for $180,000 cash on delivery not later than June 1." By coincidence, Nirvana wrote Mater a signed letter on May 1 offering to sell her "one new Mark XX Rolls-Royce sedan, with all available equipment, for $180,000 cash on delivery not later than June 1." These letters crossed in the mails and were respectively received and read by Mater and Nirvana on May 2. If Mater subsequently asserts and Nirvana denies that the parties had a binding contract on May 3, which of the following most persuasively supports Mater's position? 
A sale-of-goods contract may be made in any manner sufficient to show agreement, even though the moment of its making is undetermined.  A sale-of-goods contract does not require that an acceptance be a mirror image of the offer. With respect both to the making of an agreement and the requirement of consideration, identical cross-offers are functionally the same as an offer followed by a responsive acceptance.  Since Nirvana was a merchant in the transaction and Mater was not, Nirvana is estopped to deny that the parties' correspondence created a binding contract. 