Determine whether \(\mathbf{u}\) is orthogonal, parallel or neither to
\(\mathbf{v}\) :
$$\begin{aligned}
&\mathbf{u}=\left(\begin{array}{c}
-\frac{1}{2} \\
2
\end{array}\right), \mathbf{v}=\left(\begin{array}{c}
-2 \\
\frac{1}{2}
\end{array}\right)\\\
& \mathbf{u}=\left(\begin{array}{l}
8 \\
4
\end{array}\right), \mathbf{v}=\left(\begin{array}{c}
6 \\
-12
\end{array}\right)\\\
&\mathbf{u}=\left(\begin{array}{c}
2 \sqrt{3} \\
2
\end{array}\right), \mathbf{v}=\left(\begin{array}{c}
1 \\
-\sqrt{3}
\end{array}\right)
\end{aligned}$$