Kirk has contracted to deliver to Doolittle 1,000 cases of Wonder brand beans on or before October 1. Doolittle is to specify means of transportation 20 days prior to the date of shipment. Payment for the beans is to be made by Doolittle on tender of delivery. On September 10, Kirk prepares the 1,000 cases for shipment. Kirk asks Doolittle how he would like the goods to be shipped, but Doolittle does not respond. On September 21, Kirk, in writing, demands assurance that Doolittle will be able to pay on tender of the beans, and Kirk asks that the money be placed in escrow prior to October 1 in a bank in Doolittle's city named by Kirk. Doolittle does not respond to any of Kirk's requests, but on October 5 he wants to file suit against Kirk for breach of contract for failure to deliver the beans as agreed. Explain Kirk's liability for failure to tender delivery on October 1.