Lee Dennegar and Mark Knutson lived in Dennegar’s house in Raritan, New Jersey. Dennegar paid the mortgage and other household expenses. With Dennegar’s consent, Knutson managed their household’s financial affairs and the “general office functions concerned with maintaining the house.” Dennegar allowed Knutson to handle the mail and “to do with it as he chose.” Knutson wrote checks for Dennegar to sign, although Knutson signed Dennegar’s name to many of the checks with Dennegar’s consent. AT&T Universal issued a credit card in Dennegar’s name in February 2001. Monthly statements were mailed to Dennegar’s house, and payments were sometimes made on those statements. Knutson died in June 2003. The unpaid charges on the card of $14,752.93 were assigned to New Century Financial Services, Inc. New Century filed a suit in a New Jersey state court against Dennegar to collect the unpaid amount. Dennegar claimed that he never applied for or used the card and knew nothing about it. Under what theory could Dennegar be liable for the charges? Explain.