Variable costs usually change as the firm alters the quantity of output produced

Refer to Figure 12-2. Why is the total revenue curve a ray from the origin?

A) because the firm can sell its product at a constant price B) because revenue increases at a decreasing rate C) because the firm must lower its price to sell more D) because revenue increases at an increasing rate

The ability of a monopoly to charge a price that exceeds marginal cost depends on

A) the price elasticity of supply. B) price elasticity of demand. C) slope of the demand curve. D) shape of the marginal cost curve.