?? ? ??????5.4??????????
????:1?????????:???????
2???????
3???????
4???51
5?????vx
??????????11?22?????????? ?,?22??,?5.4????????????,?????“?”?
?,????22?????????18???????????45??????????????20??22????20??????????????????40??????20??43??21??29?,?20??40??????????5.4??,???23.2?????120.18?,???????23.2????????,???????7.7??
????,??,????????????,???????,?“???????????????”????,?????????????
?????,?“??????????”,?“??????????????????”?
??,22??????????20?????40???????????????????4.7???????(??????????) ?????:??