A Random Sample of 9 TI-89 Titanium Calculators Being Sold $\begin{array}{lllll}\hline 142 & 149 & 147 & 146 & 145 \\\hline 148 & 154 & 136 & 131 & \\\hline\end{array}$

A random sample of 9 TI-89 Titanium calculators being sold over the internet had the foll prices, in dollars.
$\begin{array}{lllll}\hline 142 & 149 & 147 & 146 & 145 \\\hline 148 & 154 & 136 & 131 & \\\hline\end{array}$
Assume the population standard deviation is $\sigma = 30$ and that the population is approximat normal. Construct a $95 \%$ confidence interval for the mean price for all the TI-89's being sold over the internet. owing

A) (139.7, 148.8)
B) (136.9, 151.6)
C) (124.6, 163.8)
D) (85.4, 203.0