A radio frequency identification device comprises an integrated circuit including a receiver, a transmitter, and a microprocessor. A new call admission judgment unit controls admission of a call from a new mobile station based on a packet allocation frequency for satisfying an existing terminal target transmission data rate relating to a plurality of mobile stations and a packet allocation frequency for satisfying a new terminal target transmission data rate relating to a new mobile station. A bypass conduit connected in parallel with the water purification units and valves permit system maintenance during which the water from the supply can flow directly to the point of use. The activating agent is initially present as a solid substance or a mixture or a plurality of such substances, which reacts in aqueous solution as an acid or base. Other embodiments are also disclosed. The one-stop shopping system and method provide objective information for the system enrollee to assess and decide on health-care insurance and services.