Question
If $\vec{\text{a}}$ is a non-zero of magnitude 'a' and $\lambda$ is a non-zero scalar, then $\lambda\vec{\text{a}}$ is a unit vector if:
- $\lambda=1$
- $\lambda=-1$
- $\text{a}=|\lambda|$
- $\text{a}=\frac{1}{|\lambda|}$