Score-It, Inc., is a large manufacturer of video games. The marketing research department is designing a survey to determine attitudes toward the products. Additionally, the percentage of households owning video games and the average usage rate per week are to be determined. The department wants to be 95% confident of the results and does not want the error to exceed +/-3 percentage points for video game ownership and +/-1 hour for average usage rate. Previous reports indicate that about 20 percent of the households own video games and the average usage rate is 15 hours with a standard deviation of 5 hours. a) What sample size would you recommend, assuming only the percentage of households owning video games is to be determined? (20 points) b) What sample size would you recommend, assuming only the average usage rate per week is to be determined? (20 points) c) What sample size would you recommend overall, assuming both variables are to be determined? (20 points) After the survey was conducted, the results indicated that 30% of the households owned video games, and the average usage rate was 13 hours with a standard deviation of 4 hours. (Use the sample size you recommend in part "c)" in answering the questions below.)