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????? ?????? ??? ???? ???? ??????? ????? ? ????? , ??? ????? ???? ?? ??????? ??????. ????? ????? ?????? ??????? ?? ?????? ?????? ???? ?? ??????? ???????? ?? ????? ???? ???? .

???? ?????? , ???? (Barter), ??? ???? ??? ?? ?? ??? ?? ???? ??? ????. ???? ?????? ???????? ?? ???? ??????? ??? ??? ????? ????? ??????, ??????? ?????? ????? ??????.

????? ?????? ?????? ????? ????? ??????? ? ?????? , ???????? ??? ????? ???? ? ???? ?????. ????? ????? ?????? ???????? , ??????? ????? ???? ???? ????? ??? ????? ?????? ???????? .

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