Answer
a.
range = 52
variance = 248.2605
standard deviation = 15.7563
b. coefficient of variation = 0.1189 * 100% = 11.89%
Work Step by Step
a. Range = Highest Value - Lowest Value = 159-107 = 52
Variance = $σ^2=(∑〖(x-μ)〗^2 )/n-1 =[∑(x^2) -(∑(x)^2/N)/n-1 =[356107-351390.1]/19 =248.2605 $
Standard Deviation = $\sqrt 248.2605 = 15.7563$
b. Coefficient of Variation=$15.7563 \div 132.55 \times 100% =11.89%$