???2?????????18????? (?????????????????? ?????)??18????????,????????????????????????,???“????????”,?????,???????????“???????”?????????????????????,???????????,??????????

???“???”???????????,??????????????????????????????????,???,??50????????(??)?,??????500???,???????????????1-3??,??0.3%-0.5%/????????,?????????,?????????????,????????,????????????????????????????,????

?????????????,“?????”???????????????????????,??????,???????,????20????????(??????????????)?????????????0.3%/??,20??0.5%/?????????????????????????????????????????????????????????

??????,??“???”?????20??(?)?,???????????????20????????,?????????????????????????,????????????????????????????????????????????(???) ?????????:???

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