Question: ========================== 21. What is the class interval? A. 5 B.6 C. 7 D. 8 22. What is the lower boundary of the highest class? A. 21 B. 25 C. 46 D. 50 23. What is the class mark of the class with the highest frequency? A. 28 B. 33 C. 38 D. 43 24. What is the cumulative frequency less than for 31-35? A. 20 B. 21 C. 22 D. 23 25. What is the cumulative frequency greater than for 36-40? A. 24 B. 25 C. 26 D.27