been determined from analyzing the records of Tim’s Brake Co. (a one-product fi rm): Contribution margin per unit $ 50 Variable cost per unit 42 Annual fi xed cost $180,000 How does each of the following measures change when product volume goes up by one unit at Tim’s Brake Co? a. Total revenue b. Total cost c. Income before tax 11. LO.2 (Break-even point) Monet’s Prints has the following revenue and cost functions: Revenue $60 per unit Cost $120,000  $30 per unit a. What is the break-even point in units? b. What is the break-even point in dollars? 12. LO.2 (Break-even point) Diamond Jim’s makes and sells class rings for local schools. Operating information is as follows: Selling price per ring $600 Variable cost per ring Rings and stones $220 Sales commissions 48 Overhead 32 Annual fi xed cost Selling expenses $180,000 Administrative expenses 105,000 Manufacturing 60,000 a. What is Diamond Jim’s break-even point in rings? b. What is Diamond Jim’s break-even point in