The Insurance Institute for Highway Safety issued a press release titled "Teen Drivers Often Ignoring Bans on Using Cell Phones" (June 9, 2008). The following quote is from the news release.Just 1-2 months prior to the ban's Dec. 1, 2006 start, 11% of teen drivers were observed using cell phones as they left school in the afternoon. About 5 months after the ban took effect, 12% of teen drivers were observed using cell phones.Suppose that the two samples of teen drivers (before the ban, after the ban) are regarded as representative of these populations of teen drivers. Suppose also that 300 teen drivers were observed before the ban (so n₁ = 300 and p₁ = 0.11) and 125 teen drivers were observed after the ban.

A) Construct a 95% large-sample confidence interval for the difference in the proportion using a cell phone while driving before the ban and the proportion after the ban. (Use p₁ p₂. Use a tableor SALT. Round your answers to three decimal places.)

(. , )

B) Interpret the interval?

There is a 95% chance that the true mean proportion of teenagers using a cell phones before the ban falls directly in the middle of this interval.

We are 95% confident that the true mean proportion of teenagers using a cell phones after the ban falls within this interval.

There is a 95% chance that the true difference between the proportions of teenagers using a cell phones before and after the ban falls directly in the middle of this interval.

We are 95% confident that the true difference between the proportions of teenagers using a cell phones before and after the ban falls within this interval.

We are 95% confident that the true mean proportion of teenagers using a cell phones before the ban falls within this interval.

C) Is 0 included in the confidence interval of part (a)? What does this imply about the difference in the population proportions?

Zero is included in the interval. This tells us that we have convincing evidence at the 0.05 confidence level of a difference between the proportion of teenagers using cell phones before and after the ban.

Zero is not included in the interval. This tells us that we have convincing evidence at the 0.05 confidence level of a difference between the proportion of teenagers using cell phones before and after the ban.

Zero is not included in the interval. This tells us that we do not have convincing evidence at the 0.05 confidence level of a difference between the proportion of teenagers using cell phones before and after the ban.

Zero is included in the interval. This tells us that we do not have convincing evidence at the 0.05 confidence level of a difference between the proportion of teenagers using cell phones before and after the ban.