Zero vector can be considered as a scalar because its magnitude is zero and direction is not defined.
Which of the following is true about multiplication of a vector by a scalar.
1) Scalar multiplication by a positive number other than 1 changes its magnitude but not direction.
2) Scalar multiplication always lead to change in magnitude and direction.
3) Scalar multiplication by -1 will not change the magnitude of the vector but will change its direction.
4) Scalar multiplication by a negative number other than -1 will reverse its direction and change its magnitude as well.