You need to familiarize yourself with standard deviation and mean values in order to attempt this problem.

The normal distribution is a pattern for the distribution of data which follows a bell-shaped curve. The normal distribution is called normal because the data points are concentrated in the center near the mean, the data does not usually contain extreme values, and the probability of deviations of the data points from the mean are (nearly) identical in either direction. Graphically, the normal distribution looks like the following:

Where 0 is the mean, and \(0+ \sigma\) and \(0- \sigma\) designate one standard deviation greater and less than the mean. The percentage values in the above figure indicate what percentage of the data fall into that region.

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Sandy

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