The following histogram represents quiz scores and uses the interval bins: 1-5, 6-10, 11-15, 16-20, 21-25, 26-30, 31-35, and 36-40. For students who earned a score of 20 or lower on the quiz, the cumulative frequency is __________ and the relative cumulative frequency is __________. a.) 29; 58% b.) 16; 32% c.) 9; 18% d.) 38; 76%.