A charge q=-820nC is uniformly distributed on a ring of 2.4 m radius. A charge q=+530nC is placed at the center of the ring. Points A and B are...

A charge q=-820nC is uniformly distributed on a ring of 2.4 m radius. A charge q=+530nC is placed at the center of the ring. Points A and B are located on the axis of the ring, at distances of 1.8m and 3.2M, respectively. The work done by an external force that transports an electron from B to A is closest to:a. 540eVb. 45eVc. -540eVd. 630eVe. -45eV