Use the Frequency Distribution to Find the Mean and the Sample

Multiple Choice

Use the frequency distribution to find the mean and the sample standard deviation. Does the data form a normal distribution? Remember: if the data fall within 2% of the empirical rule of 68%, 95%, and 99.7% for one, two, or three standard deviations, respectively, they form a normal distribution.   $\begin{array}{|ccc|}\hline \text { Interval } & \text { Midpoint x }& \text {Frequency t }\\\hline42.5-50.5 && 9 \\50.5-58.5 && 45 \\58.5-66.5 && 205 \\66.5-14.5 && 190 \\14.5-82.5 && 44 \\82.5-90.5 && 20\\\hline\end{array}$

A) The mean is 62. The sample standard deviation is 9.2. The data doesn't form a normal distribution.
B) The mean is 60. The sample standard deviation is 6.2. The data doesn't form a normal distribution.
C) The mean is 60. The sample standard deviation is 6.2. The data forms a normal distribution.
D) The mean is 67. The sample standard deviation is 7.7. The data doesn't form a normal distribution.
E) The mean is 67. The sample standard deviation is 7.7. The data forms a normal distribution.