The formula for the standard deviation \( \sigma \) of a data set \( x_1, x_2, \dots, x_n \) is:
\[
\sigma = \sqrt{\frac{1}{n} \sum_{i=1}^{n} (x_i - \mu)^2},
\]
where \( \mu \) is the mean of the data set. First, find the mean:
\[
\mu = \frac{2 + 4 + 6 + 8 + 10}{5} = 6.
\]
Now, calculate the variance:
\[
\text{Variance} = \frac{1}{5} \left( (2 - 6)^2 + (4 - 6)^2 + (6 - 6)^2 + (8 - 6)^2 + (10 - 6)^2 \right) = \frac{1}{5} (16 + 4 + 0 + 4 + 16) = \frac{40}{5} = 8.
\]
The standard deviation is the square root of the variance:
\[
\sigma = \sqrt{8} = 2\sqrt{2}.
\]