5. The following table shows the quantity sold of a monopolist's product at different prices. Calculate Total Revenue and Marginal Revenue and fill the form. Also, comment on the relationship between total revenue and marginal revenue from the table. (12 points) Quantity (units) Price ($) Total Revenue ($) | Marginal Revenue ($) 0 10 10 9 20 8 30 J 40 6 50 5 60 70 80 H N 90 6. Differentiate between an oligopoly and a monopolistic competition on the basis of the number of firms and the degree of product differentiation. (10 points) 7. Why is there emphasis on nonprice competition in oligopoly? (12 points)