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

????????11?????26? ????“??”??,?????????????25?????,????????????“?????????????”,?????????????????,??(?????,75?)??????????????,????????????????????????

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

??????????????:“??????”??????? ???????????????:?? “?????200????”_????

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

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

2?????vx

3?????????

4???????

5????????

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

????????11?????26? ????“??”??,?????????????25?????,????????????“?????????????”,?????????????????,??(?????,75?)??????????????,????????????????????????

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

??????????????:“??????”??????? ???????????????:??