?? ??????? ???????28?(????)??

????:1???????V:??????
2????????
3???50????????
4???????
5???????
??2?????????20???????? (????????????)?????20?????????,2?????1????,????????????,?28?(?????????????????????)?????????
2?????1???,?????????34???,??,??,??;???????????7.3?,?????0.8????????????,2???????12?,??????????

????,???????,?????????????,??,??????????????????????????22????????23???,??????????????????????30?????????????50?,?????????????20??????30???
?,?(????????)?????,???????,????,?,???????,????(?)
??????????????????:????????