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

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

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

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

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