The above table shows some cost data for Tracey's Tents. What is the marginal cost of the 3rd tent?

An exclusive deal is

A) always illegal. B) welfare reducing. C) one where a firm will only sell to a customer if the customer agrees not to buy anything from the firm's rivals. D) All of the above.

The opportunity cost of an activity

a. depends on the individual's subjective values and opinions b. is the same for everyone c. must be calculated and known before undertaking that activity d. is irrelevant to decision making e. is not influenced by time costs