Two point charges, 3q and −q, are separated by a distance a. For each of the arrangement...

Two point charges, 3q and −q, are separated by a distance a. For each of the arrangements in Fig. 3.35, find (i) the monopole moment, (ii) the dipole moment, and (iii) the approximate potential (in spherical coordinates) at large r (include both the monopole and dipole contributions).