Part 1
To find the range, we subtract the lowest value from the greatest value, ignoring the others.
So, in this case, we have:
• Lowest value: 20.3
,
• Greatest value: 110.4

Therefore, the range is 90.1
Part 2The formula to find the variance is

The formula to find the mean is

So, as you can see, we first find the mean, and with this value, we find the variance of the data set.
• Mean

• Variance
![\begin{gathered} \sigma=((20.3-45.32)^2+(33.5-45.32)^2+(21.8-45.32)^2+(58.2-45.32)^2+(23.2-45.32)^2+(110.4-45.32)^2+(30.9-45.32)^2+(24.4-45.32)^2+(74.6-45.32)^2+(60.4-45.32)^2+(40.8-45.32)^2)/(11) \\ \sigma=((-25.02)^2+(-11.82)^2+(-23.52)^2+(12.88)^2+(-22.12)^2+(65.08)^2+(-12.42)^2+(-20.92)^2+(29.28)^2+(15.08)^2+(-4.52)^2)/(11) \\ \sigma=(625.91+139.67+553.10+165.94+489.21+4325.64+207.88+437.57+857.42+227.46+20.41)/(11) \\ \sigma=(7960.24)/(11) \\ $$\boldsymbol{\sigma=723.66}$$ \end{gathered}]()
Therefore, the variance is 723.66.