Which answer is correct?

Park Manufacturing hired Stone as a traveling salesman to sell goods manufactured by Park. Stone also sold a line of products manufactured by a friend. He did not disclose this to Park. The relationship was unsatisfactory and Park finally fired Stone after learning of Stone's sales of the other manufacturer's goods. Stone, enraged at Park for firing him, continued to make contracts on Park's behalf with both new and old customers that were almost uniformly disadvantageous to Park. Park, upon learning of this, gave written notice of Stone's discharge to all parties with whom Stone had dealt. Which of the following is incorrect? a. Park can bring an action against Stone to have him account for any secret profits. b. Prior to notification, Stone retained some continued authority to bind Park despite termination of the agency relationship. c. New customers who contracted with Stone for the first time could enforce the contracts against Park if they knew that Stone had been Park's salesman but were unaware that Stone was fired. d. If Park had promptly published a notification of termination of Stone's employment in the local newspapers and in the trade publications, he would not be liable for any of Stone's contracts.