From a sample of 487 teenagers, a total of 385 had their pictures online. Find the standard deviation of the best estimate of the proportion of teenagers having online pictures. Note: Enter X.XXX AT LEAST ONE DIGIT BEFORE THE DECIMAL, THREE AFTER and round up. Thus, 27 is entered as 27.000, 3.5638 is entered as 3.564, 0.3754 is entered as 0.375