The magnitude of the projection of the vector $\bar {a}=4 \bar {i}-3 \bar {j}+2 \bar k $ on the line which makes equal angles with the coordinate axes is

Question

\[\begin {array} {1 1} (a)\;\sqrt 2 & \quad (b)\;\sqrt 3 \\ (c)\; \frac{1}{\sqrt 3} & \quad (d)\;\frac {1}{\sqrt 2} \end {array}\]