19. The break-even point in unit sales increases when variable expenses a. Increase and the selling price remains unchanged b. Decrease and the selling price remains unchanged c. Decrease and the selling price increases O d. Remain unchanged and the selling price increases 20. The total contribution margin decreases if sales volume remains the same and which of the following occurs? O a. Fixed expenses increase O b. Fixed expenses decrease O C. Variable expense per unit increases O d. Variable expense per unit decreases