A Gallup poll indicated that 20% of Americans had confidence in U.S. banks. Interestingly, 58% also said that they had confidence in their main or primary bank. (data extracted from D. Jacobs, "Americans' Confidence in Banks Is at Historical Low," www.gallup.com, April 7, 2010). The results are based on telephone interviews conducted March 24, 2010, with 1,006 adults living in the United States, aged 18 and older.
a. Describe the population of interest.
b. Describe the sample that was collected.
c. Is 20% a parameter or a statistic? Explain.
d. Is 58% a parameter or a statistic?