The Sullivan Statistics Survey II asks, "What percent of one's income should an individual pay in federal income taxes?" Go to www.pearsonhighered.com/sullivanstats to obtain the data file SullivanStatsSurveyII using the file format of your choice for the version of the text you are using. The data is in the column "Tax Rate."
(a) Draw a relative frequency histogram of the variable "Tax Rate" using a lower class limit of the first class of 0 and a class width of 5. Comment on the shape of the distribution.
(b) Draw a boxplot of the variable "Tax Rate." Are there any outliers?
(c) Explain why a large sample is necessary to construct a confidence interval for the mean tax rate.
(d) Treat the respondents of this survey as a simple random sample of U.S. residents. Use statistical software to construct and interpret a 90% confidence interval for the mean tax rate U.S. residents feel an individual should pay in federal income taxes?