???2?17???????? (??? ???????????)???????????17??,??,2?13?????16?,?????????????,?72????????15.3?,???????????;????????????????????????10?48?6.5?~10.9????????????,??????;????????????????????????????????????4????

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

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

????????????????2????18??????????2????22???????,?,??????????????????????,???????????2??19??2?20?????????????,???,??????????????????,??????,???,???(?????????)

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

??

??:???????????,??????????,??????????????