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

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

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

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

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