c
\(\mathop A\limits^ \to \) અને \(\mathop B\limits^ \to \,\) બંને ને લંબ એક્મ સદીશ \(\hat n\,\, = \frac{{\overrightarrow A \times \overrightarrow B }}{{|\overrightarrow A \times \overrightarrow B |}} = \,\,\frac{{2\hat i\,\, - \,\,6\hat j\,\, + \;\,3\hat k}}{7}\,\, = \,\,\frac{2}{7}\hat i\,\, - \,\,\frac{6}{7}\,\hat j\,\, + \;\,\frac{3}{7}\hat k\)