Biologists conducted experiments to determine whether a deficiency of carbon dioxide in the soil affects the phenotypes of peas. Listed below are the phenotype codes, where 1equalssmooth-yellow, 2equalssmooth-green, 3equalswrinkledyellow, and 4equalswrinkled-green. 2    1    2    2    3    1    4     2    2    2    2    2    2    2     2    3    1    2    2    2 Find the standard deviation of the sample data.