????:1?????????600??:??????

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

3????????????????

4???????????

5????vx

?????????????10??????????1?????????????????????? (?? ???????????????)??30??,??,??2304??,??23.7???????????,???15.7%?15.3%?

???,????15.7%??????? ?

??????,??????????7??230??????????;?(?????????????)??????530?,???????????????

?,????????????????????????60??????????????????????????????????????????????????????????????????,?????

?????,??????????????????,?????????????(?)

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