\(=[(4 \hat{ i }+3 \hat{ j }-\hat{ k })-(\hat{ i }+2 \hat{ j }+\hat{ k })] \times \overrightarrow{ F }\)
\(=(3 \hat{i}+\hat{j}-2 \hat{k}) \times(\hat{i}+2 \hat{j}+3 \hat{k})\)
\(\tau=\left|\begin{array}{ccc}\hat{i} & \hat{j} & \hat{k} \\ 3 & 1 & -2 \\ 1 & 2 & 3\end{array}\right|\)
\(=7 \hat{ i }-11 \hat{ j }+5 \hat{ k }\)
\(|\vec{\tau}|=\sqrt{195}\)