I did some googling and research to decide where I was going to research the mean income per person. I started with the United States as a whole--The mean income per person in the united states is $44,500. The distribution of incomes follows a normal distribution. A random sample of 16 residents of Wilmington, Delaware,had a mean of $52,500 with a standard deviation of $9,500.

Where did the standard deviation come from?