???????????????????????????????????????????????????????????????????????????????????????????????
??????????????????????????????????????????????????????
????????????
?40?????????????????????????????15~30???????????????????????????1~2??10??1???
??????????
?1????????????30????????????10????2????????????????????????????????????????????????????2~3??
?2??????1??????15?????????????????????????????30?????1~2??
?3????????????????????????????????30????1?????????30?????2??30??1???
?4?????????????30????10?????????15?????1500?????????????10~20?????1??
