Answer
Range:42, variance:174.5, standard deviation: 13.21.
Work Step by Step
Range is the difference of the maximum and minimum of the set: range=127-85=42. Calculated by calculator, the mean is: 101. The variance is the sum of the differences of each value and the mean on the power of two, divided by the number of values minus 1: variance=$\frac{(96-101)^2+(89-101)^2+...+(124-101)^2}{20-1}=174.5 $. The standard deviation is the square root of the variance: standard deviation=$\sqrt{174.5}=13.21$.