Answer
Variance:0.83 Standard deviation:0.91 Range:3.
Work Step by Step
The mean can be counted by summing all the data and dividing it by the number of data: $\frac{4+6⋅3+7⋅2+11⋅12}{5}=1.88$: $\mu=1.88.$ Variance=$\frac{\sum (x-\mu)^2}{n}=\frac{(2-1.88)^2+(1-1.88)^2+...+(2-1.88)^2}{25}=0.83.$ Standard deviation=$\sqrt{variance}=\sqrt{0.83}=0.91$ Range=maximum value-minimum value=4-1=3$.