[16] Which of the following weaken the ability of firms to form a cartel? A. Firms have high inventories B. There are a large number of firms attempting to cooperate C. Firms sell a homogeneous product D all of the above [17] The Herfindahl index in the case of monopolistic competition: A. equals 10,000. B. equals 0. C. exceeds 10,000. D lies between 0 and 10,000