1. \(\overline{OA} \times \overline {OB}\) =
= 14i – j – 4k
Base area = |l4i – j – 4k|
= \(\sqrt{196+1+16} = \sqrt{213}\)
2. Volume of the parallelopiped is
= (14i – j – 4k).(2i + 3 j + k)
= 28 – 3 – 4 = 21.
3. Height = \(\frac{volume}{base\, area}\) = \(\frac{21}{\sqrt{23}}\).