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

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

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

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

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