7 The potential energies associated with four orientations of an electric dipole in an electric field are (1) -5Up, (2) -7U, (3) 3U0, and (4) 5Uo, where Uo is positive. Rank the orientations according to (a) the angle between the electric dipole moment p and the elec- tric field E and (b) the magnitude of the torque on the electric dipole, greatest first.