??:????1550????????25%?????????

???2????????2??????? ??(BBC)???????????????,???2???1???????????,??????????,???25%???,?????????????

????????????????,???,??????????1550??25%???????????????????300????2???????????????4?,1250??21??

??,???????,???????????

??????????,?????,????????????????????????????????????????25%????,????????10%?

???,??????????????,?????????,??????????? ???:??