Which of the following set of molecules will have
zero dipole moment ?
(1) Ammonia, beryllium difluoride, water,
1,4-dichlorobenzene
(2) Boron trifluoride, hydrogen fluoride, carbon
dioxide, 1,3-dichlorobenzene
(3) Nitrogen trifluoride, beryllium difluoride,
water, 1,3-dichlorobenzene
(4) Boron trifluoride, beryllium difluoride,
carbon dioxide, 1,4-dichlorobenzene