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

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

3?????????

4?????vx

5??????????

?? ? ???????????????

?????????????????????????????????2????7????????? (? ? ???????????????)?2?7?,?????,???????????????????????????257?????,???170?????(??????85?),?6??????????64?????170???23???,?40??????,???16???,????????147??????????????????????????(???)

??:????