The drawing shows a graph of a set of equipotential surfaces

The drawing shows a graph of a set of equipotential surfaces seen in cross section. Each is labeled according to its electric potential. A +7.3 10-7 C point charge is placed at position A. Find the work that is done on the point charge by the electric force when it is moved about the the following ways

a)
work done = q* (VB -VA)
=7.3 *10-7 * (550-350)
= 1.46 * 10-4 J

B)
work done = q* (VC -VA)
=7.3 *10-7 * (350-350)
= 0 J