Answer:
The standard deviation = 7.65
The variance = 58.55
Step-by-step explanation:
The given data are:
x = 19.9, 3.7, 24.6, 4.9, 13.5, 4.4, 19, 18.1
The mean is calculated as:

The standard deviation is given by the formula:
![\begin{gathered} SD=\sqrt{(\sum(x-\mu)^2)/(N)} \\ SD=\sqrt{((19.9-13.5125)^2+(3.7-13.5125)^2+(24.6-13.5125)^2+(4.9-13.5125)^2+(13.5-13.5125)^2+(4.4-13.5125)^2+(19-13.5125)^2+(18.1-13.5125)^2)/(8)} \\ SD=7.65 \end{gathered}]()
The variance = SD²
The variance = 7.65²
The variance = 58.55