Firms like McDonalds and Wendy sell hamburgers, salads, and other products that are differentiated in nature. While numerous fast-food restaurants exist in most locations, the differentiated nature of the firm’s products permits them to charge prices that are in excess of marginal cost. Given these observations, is the fast-food industry most likely a perfectly competitive industry, a monopoly, monopolistically competitive, or an oligopoly? Use the causal view of structure, conduct, and performance to explain the roles of product differentiation in the industry, and explain how the feedback critique applies in this context