11??21???????,?????????-19.6?,???????“????????”??????????????,???,??

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

(??????????????? ???? ???? ?????????? ???? ?????????? ????????)

??:?????

??“??????200??”????

?? ??“????????”????

????:1???????200??:?????100?

2???95?

3????????vx

4??????150????

5???????

11??21???????,?????????-19.6?,???????“????????”??????????????,???,??

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

(??????????????? ???? ???? ?????????? ???? ?????????? ????????)

??:?????