Private Colleges and Universities Rely on Money Contributed by Individuals $122.6,177.5,95.4$

Private colleges and universities rely on money contributed by individuals and corporations for their operating expenses. Much of this money is invested in a fund called an endowment, and the college spends only the interest earned by the fund. A recent survey of eight private colleges in the United States revealed the following endowments (in millions of dollars) : 60.2, 47.0, 235.1, 490.0, $122.6,177.5,95.4$ , and 220.0. Summary statistics yield $\bar { x } = 180.975$ and $s = 143.042$ . Calculate a $99 \%$ confidence interval for the mean endowment of all private colleges in the United States.

A) $180.975 \pm 189.173$
B) $180.975 \pm 169.672$
C) $180.975 \pm 181.387$
D) $180.975 \pm 176.955$