Question: An HR manager in a large company is interested in the mean missing days of work this year by all the employees. A random sample of 16 employees produced a mean of missing 6.2 days of work and a standard deviation of 2.5 days. Assume the distribution of missing days of work this year follows a normal distribution.

a) Compute a 95% confidence interval for the mean missing days of work this year by all the employees.

b) Interpret the interval from part a) in the context of the problem.

c) Without calculating it, will be 99% confidence interval be wider or narrower?