Bye Bye telegraphed Vendor on June 1, "At what price will you sell 100 of your QTModel garbage-disposal units for delivery around June 10?" Thereafter, the following communications were exchanged: 1. Telegram from Vendor received by Bye Bye on June 2: "You're in luck. We have only 100 QT's, all on clearance at 50% off usual wholesale of $120 per unit, for delivery at our shipping platform on June 12." 2. Letter from Bye Bye received in U.S. mail by Vendor on June 5: "I accept. Would prefer to pay in full 30 days after invoice." 3. Telegram from Vendor received by Bye Bye on June 6: "You must pick up at our platform and pay C.O.D." 4. Letter from Bye Bye received in U.S. mail by Vendor on June 9: "I don't deal with people who can't accommodate our simple requests." 5. Telegram from Bye Bye received by Vendor on June 10, after Vendor had sold and delivered all 100 of the QT's to another buyer earlier that day: "Okay. I'm over a barrel and will pick up the goods on your terms June 12." Bye Bye now sues Vendor for breach of contract. Which of the following arguments will best serve Vendor's defense? 
Vendor's telegram received on June 2 was merely a price quotation, not an offer.  Bye Bye's letter received on June 5 was not an acceptance because it varied the terms of Vendor's initial telegram. Bye Bye's use of the mails in response to Vendor's initial telegram was an ineffective method of acceptance. Bye Bye's letter received on June 9 was an unequivocal refusal to perform that excused Vendor even if the parties had previously formed a contract.