Which of the following is a dimension of volt?

$A$ potential at a point $A$ is $-3 \ V$ and that at another point $B$ is $5 \ V$. What is the work done in carrying a charge of $5 \ mC$ from $B$ to $A$?

$A$ uniform electric field exists in the positive $x$-direction. Let $A$ be the origin. Point $B$ is at $x = +1 \ cm$ on the $x$-axis and point $C$ is at $y = +1 \ cm$ on the $y$-axis. Which of the following relations is correct regarding the potentials at $A, B,$ and $C$?

The electric potential at the centre of two concentric half rings of radii $R_1$ and $R_2$,having the same linear charge density $\lambda$,is $(\varepsilon_0 = \text{permittivity of free space})$

$A$ charge $q$ is placed at the centre $O$ of a circle of radius $R$. Two other charges $q$ and $q$ are placed at the ends of the diameter $AB$ of the circle. The work done to move the charge at point $B$ along the circumference of the circle to a point $C$ as shown in the figure is

If the electric potential of the inner shell of radius $a$ is $10\,V$ and that of the outer shell of radius $2a$ is $5\,V$,then the potential at the centre will be.....$V$