A poll asked for? people's opinion on whether closing local newspapers would hurt civic? life; 428 of respondents said it would hurt civic life a lot.
Complete parts a through d below.
a. Find the proportion of the respondents who said that closing local papers would hurt civic life a lot. ?(Round to three decimal places as? needed.)
b. Find a? 95% confidence interval for the population proportion who believed closing newspapers would hurt civic life a lot. Assume the poll used a simple random sample? (SRS). (In? fact, it used random? sampling, but a more complex method than? SRS.) left parenthesis nothing comma nothing right parenthesis, ?(Round to three decimal places as? needed.)
c. Find a?n 80% confidence interval for the population proportion who believed closing newspapers would hurt civic life a lot. ?(Round to three decimal places as? needed.)
d. Which interval is wider and why?