A poll asked for people's opinion on whether closing local newspapers would hurt civic life; 427 of 1005 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.
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 (Sits). (In fact, it used random sampling, but a more complex method than SRS.)
c. Find an 80% confidence interval for the population proportion who believed closing newspapers would hurt Civic life a lot.
d. Which interval is wider and why?
OA. The 95% interval is wider. To get a higher degree of certainty, the interval needs to be widened just on the left side.
OB. The 80% interval is wider. To get a higher degree of certainty, the interval needs to be widened.
OC. The 95% interval is wider. To get a higher degree of certainty, the interval needs to be widened.
OD. The 95% interval is wider. To get a higher degree of certainty, the interval needs to be widened just on the right side.