Overweight Men For a random sample of 60 over-
weight men, the mean of the number of pounds that they
were overweight was $30 .$ The standard deviation of the
population is 4.2 pounds.
$$
\begin{array}{l}{\text { a. Find the best point estimate of the average number of }} \\ {\text { excess pounds that they weighed. }} \\ {\text { b. Find the } 95 \% \text { confidence interval of the mean of }} \\ {\text { these pounds. }}\end{array}
$$
$$
\begin{array}{l}{\text {c. Find the } 99 \% \text { confidence interval of these pounds. }} \\ {\text { d. Which interval is larger? Why? }}\end{array}
$$