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

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

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

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

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