?????? A ?-?????? ???? ??????? ????, ?? ?? combined ?????? ??? ?????? ????? ?????? ?????? ??????. ????? ????? ?-????? ?? ???????? ???, ????? ???????? ???? ???? ?? ??????? ??? ???. ??? ?????? A ???? ??????? ?? ??????, ????? ??????, ???????? ??? ??????(B3) ???? ?????? ?? ??????, ?-??????} ???? ?-????? ????. ????????? ?????? : ?????? A ????