MCQ
Which of the following is a correct relation
- A$_a{\mu _r} = {\,_a}{\mu _w} \times \,{\,_r}{\mu _\omega }$
- B$_a{\mu _r} \times {\,_r}{\mu _w} = {\,_w}{\mu _a}$
- C$_a{\mu _r} \times {\,_r}{\mu _a} = 0$
- ✓$_a{\mu _r}/{\,_w}{\mu _r} = {\,_a}{\mu _w}$

