Matlab script for statistics

(See attached file for full problem description)

Any help is greatly appreciated, as the script I wrote does not seem to be deciphering between the two sets of data.

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Write a Matlab script using the "randn" command to generate a vector of 10,000 random numbers that are normally distributed around zero, with a variance of 1. Use the "hist" command to plot a histogram of these data, specifying 50 bins. Use "find" command to determine what percentage of the data points lie within 1 standard deviation of the mean (which is zero). Redo this analysis for a smaller set of data (20 points) and reduce number of bins in the histogram.
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