Is electrostatic potential a scalar quantity or a vector quantity?

If $2 \times 10^{-3} \text{ J}$ of work is done in moving a particle carrying a charge of $10 \times 10^{-6} \text{ C}$ from infinity to a point $P$, what will be the potential at the point $P$ (in $\text{ V}$)?

What is potential difference? Is it a scalar quantity or a vector quantity? Give its $SI$ units.

What is meant by saying that the potential difference between two points is $1$ $V$?

How much energy is given to each coulomb of charge passing through a $6\, V$ battery (in $, J$)?

Which of the following represents voltage?