Pictured below are three point charges spaced equidistantly. All three charges have the same magnitude of charge Q, but the charge on the far right is negatively charged (that is, -Q). Rank the potential energy, from highest to lowest potential energy, at the four points indicated if a negative charge (-q) was to be placed there. Highest Potential Energy +Q +Q Q A K-d K d - d d K d - d Lowest Potential Energy UA UB Uc Up