List three pieces of criteria that economists use to determine if someone is employed

Why is the type of product sold in an industry an important characteristic? a firm that can differentiate its product from that of rivals may be able to charge a higher price for a superior product. a firm that sells intangible goods is usually considered a monopoly. service industries cannot differentiate their products, which makes it easy for new firms to enter the industry. expensive products are usually sold by perfectly competitive firms.