Rank the following interactions between charged particles from lowest to highest potential energy based on Coulomb's law.
(i) a 1+ charge and a 1− charge with a 117 pm distance between them
(ii) a 2+ charge and a 1− charge with a 119 pm distance between them
(iii) a 1+ charge and a 2− charge with a 117 pm distance between them
(iv) a 2+ charge and a 2− charge with a 119 pm distance between them