For each problem, select the best response. (a) A survey records many variables of interest to the researchers conducting the survey. Below are some of the variables from a survey conducted by the U.S. Postal Service. Which of the variables is categorical? .A. A. County of residence. iAi B. Age of respondent. .A c. Total household income, before taxes, in 1993. .A. D. Number of people, both adults and children, living in the household. A E. None of the above. (b) A description of different houses on the market includes the following three variables. Which of the variables is quantitative? .A. A. The monthly electric bill. .A. B. The exterior paint colors. .A. c. The street number. A D. The school district. A E. None of the above. (0) A description of different houses on the market includes the following three variables. Which of the variables is quantitative? .A. A. The monthly electric bill. .A. B. The exterior paint colors. .A. c. The street number. A D. The school district. .A. E. None of the above. Note: You can earn partial credit on this