Having trouble understanding how they got these answers.

2.1.19 Question Help Construct one table that includes relative frequencies based on the frequency distributions shown below, then compare the amounts of tar in nonfiltered and filtered cigarettes. Do the cigarette filters appear to be effective? (Hint: The filters reduce the amount of tar ingested by the smoker.) Click the icon to view the frequency distributions. Complete the relative frequency table below. Relative Relative Frequency Frequency Tar (mg) (Nonfiltered) (Filtered) 3-7 0% 12% X 8 - 12 0% 8 % X That's incorrect. 13 -17 8% 20% 18-22 0% 60% 23-27 52% Correct answer: C 0% 28 - 32 24% 0% Your answer: A 33 - 37 16% 0% (Simplify your answers.) Similar Question Next Question Do cigarette filters appear to be effective? O A. No, because the relative frequencies for each are not substantially different. O B. No, because the relative frequency of the higher tar classes is greater for filtered cigarettes. C. Yes, because the relative frequency of the higher tar classes is greater for nonfiltered cigarettes. O D. This cannot be determined. Click to select your answer and then click Check