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

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

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

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

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