plz help with these questions

18. Which of the following will have no effect on the break-even point in units? A) The selling price increases. B) The variable cost per unit increases. C) The number of units sold declines. D) Total fixed costs increase. 19. Which of the following statements regarding the contribution margin ratio is not true? A) The contribution margin ratio is equal to the contribution margin per unit divided by the selling price per unit. B) The contribution margin ratio is the amount of each sales dollar that goes toward covering fixed costs and generating a profit. C) The contribution margin ratio is equal to variable cost per unit divided by fixed cost per unit. D) The contribution margin ratio is useful when companies that sell a variety of products calculate a break-even point in sales. 20. Sympli Staples produces a single stapler that it sells for $15 per unit. If variable costs per unit are $6 and fixed costs total $42,300, how many units must the company sell in order to earn a profit of $12,150 ? A) 3,350 units B) 4,700 units C) 3,630units D) 6,050 units 21. Road Master Racers makes toy race cars that sell for $12 each with a variable cost ofs5 per car. Annual fixed costs are $7,000. How much will profit increase if 600 more units are sold? A) $7,200 B) $4,200 C) $1,000