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

2???????

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

4??????????

5???????

????2??????????17??? ????(???????????“?????????????”)17??????????,????????37.7%????????????,??2???

??????????????????????????????????,????????????????????,??????????????????“???”,??????????????

???????????,??????35??,????????5??????????????????,??????,?,??????????????,??

???????????,?????????,??????(54.3%)????????????????????????,?2?,??????????????3.5?????????????

?,????,????????????????,??????????(46.6%)??????????????

?????????“???????????????????”???,??,??????12?????17????????????????12.5%?18.4%,?????????????,??????????????(?????????????????) ??????????:?????????????