Below You Are Given Ages That Were Obtained by Taking $\mu$

Below you are given ages that were obtained by taking a random sample of 9 undergraduate students. Assume the population has a normal distribution.
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a.What is the point estimate of $\mu$ ?
b.Determine the standard deviation.
c.Construct a 90% confidence interval for the average age of undergraduate students.
d.Construct a 99% confidence interval for the average age of undergraduate students.
e.Discuss why the 99% and 90% confidence intervals are different.