????:1?????:?????vx?????

2?????????????

3?????????

4???????

5????????????

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

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

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

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

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