Question 2: What would you estimate the standard deviation of height to be?
The mean height for this sample is 164.5 cm and the standard deviation is 6.8 cm. The distribution is fairly symetrical so we expect the mean to be in the middle, the majority of observations to be within one standard deviation on either side of the mean, and nearly all observations to be within two standard deviation on either side of the mean. Because the distribution is symmetrical, We expect a little of the histogram to beyond the mean plus or minus two standard deviations limits at either end of the distribution.
The following figure shows this to be the case:
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