In a random sample of 8 people, the mean commute time to work was 33.5 minutes and the standard deviation was 7.3 minutes. A 95% confidence interval using the t-distribution was calculated to be...

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Extracted text: In a random sample of 8 people, the mean commute time to work was 33.5 minutes and the standard deviation was 7.3 minutes. A 95% confidence interval using the t-distribution was calculated to be (27.4,39.6). After researching commute times to work, it was found that the population standard deviation is 9.6 minutes. Find the margin of error and construct a 95% confidence interval using the standard normal distribution with the appropriate calculations for a standard deviation that is known. Compare the results. ..... The margin of error of u is: (Round to two decimal places as needed.) A 95% confidence interval using the standard normal distribution is ( | D (Round to one decimal place as needed.) Compare the results. Choose the correct answer below. O A. The confidence interval found using the standard normal distribution is wider than the confidence interval found using the student's t-distribution. O B. The confidence interval found using the standard normal distribution has smaller lower and upper confidence interval limits. O C. The confidence interval found using the standard normal distribution is the same as the confidence interval found using the student's t-distribution. O D. The confidence interval found using the standard normal distribution is narrower than the confidence interval found using the student's t-distribution.