I have a wireless router in one building (BuildingA) which contains the main cable modem box. I would like to shoot internet to another building (BuildingB) just 25 feet away. BuildingB contains some additional computers, is it possible to have a wireless router in BuildingB whichs uses it antenna to pickup the signal from wireless router in BuildingA and then feed the network to the computers in BuildingB via its cat5 connections?

Sorry for confusions! Would rather not buy wireless network cards for the computers in BuildingB.