High-Low Method The manufacturing costs of Rosenthal Industries for the first three months of the year follow: Total Costs Production January $146,880 800 units February 180,170 1,570 March 228,480 2,400 Using the high-low method, determine (a) the variable cost per unit and (b) the total fixed cost. a. Variable cost per unit b. Total fixed cost $ Contribution Margin Sally Company sells 39,000 units at $41 per unit. Variable costs are $24.60 per unit, and fixed costs are $217,500. Determine (a) the contribution margin ratio, (b) the unit contribution margin, and (c) operating income. a. Contribution margin ratio (Enter as a whole number.) % b. Unit contribution margin (Round to the nearest cent.) $ per unit c. Operating income