Find the Mean for the Given Sample Data $\begin{array} { l l l } 52 & 67 & 66 \end{array}$

Multiple Choice

Find the mean for the given sample data. Unless otherwise specified, round your answer to one more decimal place than that used for the observations.
-Last year, nine employees of an electronics company retired. Their ages at retirement are listed below. Find the mean retirement age.
$\begin{array} { l l l } 52 & 67 & 66 \end{array}$
$\begin{array} { l l l } 52 & 64 & 58 \end{array}$
$\begin{array} { l l l } 59 & 57 & 51 \end{array}$

A) $58.0$
B) $57.2$
C) $58.4$
D) $57.8$