Read the following paragraph and answer the questions that follow.

This energy possessed by a system of charges by virtue of their positions. When two like charges lie infinite distance apart, their potential energy is zero because no work has to be done in moving one charge at infinite distance from the other.

In carrying a charge q from point A to point B, work done W = q(VA – VB). This work may appear as change in KE/PE of the charge. The potential energy of two charges q1 and q2 at a distance r in air is \(\frac{q_1 q_2}{4\pi \epsilon_0 r}.\) It is measured in joule. It may be positive, negative or zero depending on the signs of q1 and q2.
Calculate work done in separating two electrons form a distance of 1 m to 2 m in air, where e is electric charge and k is electrostatic force constant.
(a) ke2
(b) e² /2
(c) –ke² /2
(d) zero