Answer
${\bf u}\times{\bf v}$ has length $0$ and no direction
${\bf v}\times{\bf u}$ has length $0$ and no direction
Work Step by Step
${\bf w}={\bf u}\times{\bf v}=\left|\begin{array}{lll}
{\bf i} & {\bf j} & {\bf k}\\
2 & -2 & 4\\
-1 & 1 & -2
\end{array}\right|$
$=(4-4){\bf i}-(-4+4){\bf j}+(22){\bf k}$
$={\bf 0}$
(zero vector has length 0 and no direction)
By property 3 (see "Properties of the Cross Product" box on p. 618)
${\bf v}\times{\bf u}=-{\bf w}=(-{\bf 0})={\bf 0}$
${\bf v}\times{\bf u}$ has length $0$ and no direction
