Please help! quiz due in 50 minutes!

The 95% confidence interval for the mean height of all World Campus STAT 200 students is 66.914inches to 67.633 inches. If all other factors are held constant, how would the width of the intervalchange if you constructed a 90% confidence interval?

A) The width would be decreased (i.e., it would be more narrow).

B) The width would be unchanged.

C) The width would be increased (i.e., it would be wider).

2.According to the CDC, adults should exercise at least 2.5 hours per week. In Spring 2016 data werecollected from a random sample of 522 World Campus students.A 95% confidence interval for the mean number of hours exercised per week was computed to be [3.7903, 4.6426].Is there evidence that the mean number of hours exercised by World Campus students per week is greater than the CDC's recommendation of 2.5 hours?

A) Yes, there is evidence that the mean number of hours exercised by World Campus students perweek is greater than 2.5 hours.

B) No, there is not evidence that the mean number of hours exercised by World Campus students perweek is greater than 2.5 hours.

3.Which of the following statements is true about a parameter and a statistic for samples taken from thesame population?

A) The value of the parameter varies from sample to sample.

B) The value of the statistic varies from sample to sample.

C) Both A and B are true.

D) Neither A nor B is true.

4.Suppose that length of hospital stays are independent and normally distributed with an average stay of 6.3 days and standard deviation of 2.5 days.What is the standard deviation of the distribution of sample means (i.e., standard error) for random samples of n = 100 patients?

A) 0.630 days

B) 0.025 days

C) 0.063 days

D) 0.250 days

5.In Spring 2016 data concerning shoe size were collected from a sample of 287 female World Campusstudents. In that sample, the mean shoe size was 7.977 with a standard deviation of 1.317. According toMinitab, the standard error of the mean is 0.0777.Which of the following interpretations of this standard error of the mean is correct?

A) In this sample of n=287 the standard deviation for individual shoe sizes was 0.0777

B) In the population of all female World Campus students, the standard deviation of their shoe sizes isestimated to be 0.0777

C) If we were to repeatedly pull samples of n=287 from the population of all female World Campusstudents and record each sample's mean, we could create a distribution of sample means that wouldhave an estimated standard deviation of 0.0777