Three charges are arranged in an equilateral triangle of side 108m. clockwise fromlower left they are 2 nc,4 nc and 3 nc. a: determine the voltage at the origin. what does this tell you? b: determine the electrical potential energy of the system. what does this tell you? c: imagine thatq3is moved straight vertically upward under the in uence of the other twocharges and an external force (perhaps an external force provided by you). after moving ashort distance, it is again de nitely at rest. does the external force do positive or negativework during this process? explain. determine the minimum work required by that externalforce ifq3moves a distance of 0: 5? 108m.