In a random sample of 50 people, the mean body mass index (BMI) was 27.7 and the standard deviation (s) was 6.12(Population standard deviation(sigma) is UNKNOWN. a. Construct a 99% confidence interval...

In a random sample of 50 people, the mean body mass index (BMI) was 27.7 and the standard deviation (s) was 6.12(Population standard deviation(sigma) is UNKNOWN.

a. Construct a 99% confidence interval for the population mean µ.

b. Construct a 95% confidence interval for the population mean µ. Interpret the results.

c. How does decreasing the level of confidence in part (d) change the width of the confidence interval?