????:1?????????????:???????????

2?????????

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

4???????

5?????vx

??????????2?????14?? (???????????????????? ??)?????????????????14??????????????????,????25%????????

??2??????????????10?????,????????,????????????????????????232???????,???????????

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

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