????:1???????80??:??????????

2???????

3???????

4?????

5???????

??,????????????????????50%??????????????80%?

9???28???,????????????????????????,?????????????,?,??????????

????????????????????????,??????????????,??1000???????????????1200??????,??????????????????????????????????,??D????,????

??,??????????????????????,?????????????(? ??????????????????????????????? ????????????????? ????)

??????????????:???????