||This chapter discusses many types of costs: opportunity cost, total cost, fixed cost, variable cost, average total cost, and marginal cost. Fill in the type of cost that best completes each sentence: a. What you give up for taking some action is called the ______. b. _____ is falling when marginal cost is below it and rising when marginal cost is above it. c. A cost that does not depend on the quantity produced is a(n) ______. d. In the ice-cream industry in the short run, ______ includes the cost of cream and sugar but not the cost of the factory. e. Profits equal total revenue less ______. f. The cost of producing an extra unit of output is the ______.