??????????? ??? ??????????????? ?????? ????? ????????! ????? ??????? ?? ????? ??????????? ?????? , ???? ??????????, ??? ????????? ??? ??????? ??????? N??c ta ????????? : ?????? ???????? ????? ???????? là ?????? ??? ngo?n m?c ?????? b?i môi tr??ng t??i ??p . ??? ???c phép ???????? {??????? thú