Do free electrons travel to a region of higher potential or lower potential?

$A$ hollow metal sphere of radius $5\, cm$ is charged such that the potential on its surface is $10\, V$. The potential at the centre of the sphere is

Which of the following is a volt?

$A$ non-conducting ring of radius $0.5\,m$ carries a total charge of $1.11 \times 10^{-10}\,C$ distributed non-uniformly on its circumference,producing an electric field $\vec{E}$ everywhere in space. The value of the line integral $\int_{l = \infty }^{l = 0} { - \vec{E} \cdot d\vec{l} }$ (where $l = 0$ is the centre of the ring) in volts is:

$A$ thin spherical conducting shell of radius $R$ has a charge $q$. Another charge $Q$ is placed at the centre of the shell. The electrostatic potential at a point $P$ at a distance $\frac{R}{2}$ from the centre of the shell is

Is electrostatic potential a vector or a scalar quantity?