??????“???” ?????????

????:????VX????:??????500?4???

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

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

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

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