1. Profit shall be booked in the name of husband because agreement to sell was in his name and he paid it. Having a poa in wife's name is done in delhi earlier to take care legal issues on transfer of property on poa.
2. In absence of sharing ratio,it is always assumed equal ownership. Further, there are various court judgements where in exemption has been allowed to one spouse u/s 54 if he has paid the consideration but new property is purchased in joint name. Thus, husband can claim exemotion for his entire money paid.