Answer
Sample variance = $s^{2}=4.3$
Sample standard deviation = $s =2.07$
Work Step by Step
Recall the shortcut formula for calculating the variance ($s^{2}$)$:$
$$s^{2}=\frac{\sum x_{i}^{2}-\frac{(\sum x_{i})^{2}}{n}}{n-1}$$
Let's create a table in which we compute $\displaystyle \sum x_{i}$ and $\displaystyle \sum x_{i}^{2}.$
$$ \begin{array}{rrr}
& x & x^{2}\\
\hline & -1 & 1\\
& -4 & 16\\
& -3 & 9\\
& 1 & 1\\
& -4 & 16\\
& -4 & 16\\
\hline\rm Sum & -15 & 59
\end{array}$$
Plug in the given values (there are $n=6$ data items):
$$\begin{align*}
s^{2}&= \displaystyle \frac{59-\frac{(-15)^{2}}{6}}{6-1} & & \\
& =4.3 \\\\
s&= \sqrt{17.3} =2.07
\end{align*} $$
