Don Draper and Jon Snow were both merchants in the sale of widgets. On December 1, 2017, Draper sent Snow an email offering to sell to Snow 1,000 widgets for $100 per widget, with delivery no later than December 31, 2017. It was going to take Draper about 3 weeks to manufacture the widgets. Snow sent back to Draper an acceptance of the offer, except that Snow crossed out the December 31, 2017 date and wrote into the contract a delivery date of no later than December 10, 2017. Draper received the acceptance with the change, but, knowing that he could never deliver the widgets in so short a time frame, Draper did not respond to Snow's acceptance document. Draper did not deliver any widgets to Snow on December 10 or on any other date. Snow had to go into the market and buy widgets from a different supplier for $110 per widget. Snow sued Draper for breach of contract for failing to deliver the widgets at $100 per widget. What are Draper's best arguments in defense against this lawsuit?