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

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

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

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

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