20. Using the high-low method and the information below, compute the monthly yariable cost per telephone hour for SKP Corporation. 21. Using the information in #22 above, determine the monthly fixed costs for telephone expenses SKP Corporation. 22. During this past year, a small publishing company sold 10,000 copies of Super Travel paperbacks (it's only product) at $5 per book; total fixed costs were $12,500; and total variable costs were $3 per book. What is this company's breakeven point in units