How many number of firms for perfect/pure competition, monopolistic competition, oligopoly, monopoly? How many barriers to entry for perfect/pure competition, monopolistic competition, oligopoly, monopoly? How many product differentiation for perfect/pure competition, monopolistic competition, oligopoly, monopoly?

perfect/pure Monopolistic oligopoly monopoly competition competition # of firms Barriers to entry Product differentiation Control over price example Sole proprietorship Partnership Corporation # of owners Control of decisions Ease of opening lifespan liability taxes