The projections of a vector on the three coordinate axis are $6,-3,2$ respectively. The direction cosines of the vector are:

1. A
   $6,-3,2$
2. B
   $\frac{6}{5},\frac{-3}{5},\frac{2}{5}$
3. C
   $\frac{6}{7},\frac{-3}{7},\frac{2}{7}$
4. D
   $-\frac{6}{7},\frac{3}{7},\frac{2}{7}$