8 Relative to the origin \(O\), the position vectors of the points \(A , B\) and \(C\) are given by $$\overrightarrow { O A } = \left( \begin{array} { l } 2
3
5 \end{array} \right) , \quad \overrightarrow { O B } = \left( \begin{array} { l } 4
2
3 \end{array} \right) \quad \text { and } \quad \overrightarrow { O C } = \left( \begin{array} { r }