28. Costs that will differ between altermatives and influence the outcome of a decision are A) sunk costs. B) unavoidable costs. C) relevant costs. D) product costs. 29. In determining whether planned goals are being met, a manager is performing the function of A) planning. B) follow-up. C) directing. D) controlling. 30. For an activity base to be useful in cost behavior analysis, the activity should always be stated in dollars. there should be a correlation between changes in the level of activity and changes in costs the activity should always be stated in terms of units. the activity level should be constant over a period of time. A) B) C) D) 31. Two costs at Bradshaw Company appear below for specific months of operation. Month AmountUnits Produced S 40,000 55,000 S 84,000 126,000 40,000 60,000 40,000 60,000 Delivery costs September October September October Utilities Which type of costs are these? A) B) C) D) Delivery costs and utilities are both variable. Delivery costs and utilities are both mixed. Utilities are mixed and delivery costs are variable. Delivery costs are mixed and utilities are variabl 32. A variable cost is a cost that A) varies per unit at every level of activity B) occurs at various times during the year. C) varies in total in proportion to changes in the level of activity. D) may or may not be incurred, depending on management's discretion