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

2?????300??

3?????300?2??

4???????

5??????????

??????11?????????????22??? ???22?????????,??????????????,???????????????

??????,??,??????????29?????,????????????????????????????????????15??,?????

????????,?????,?,?????????????????????????????????????,?????,??????????????818.6????,????????????????????????48.8%;???????????,???488.5??,????????????????????78.6%?

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