The table shows the total revenue of the six firms that make fine chocolates. Calculate the four-firm concentration ratio and the Herfindahl-Hirschman Index. The four-firm concentration ratio equals The HHI equals The four-firm concentration ratio indicates that the market is Herfindahl-Hirschman Index indicates that the market is and the (Assume there are no reasons that would make the concentration measures unreliable guides.) A. an oligopoly; monopolistic competition B. a monopoly; a monopoly C. a monopoly; an oligopoly D. monopolistic competition; a monopoly E. an oligopoly; an oligopoly Firm Mayfair Bond Magic All Nature Truffles Gold Industry Total revenue (dollars) 80 16 6 80 14 4 200