?? ??????????:??????600??
????:1????????????:???????
2???????
3????????????
4???????
5??????
? ????? ?????????? ????
??????????4000???????? ?“C??”
????????:????
???? 1/512??8????????,??????(???????????????????????????),??????????3.1??,????????????????????????????5000??????/??,?????????600???????????????????????,????85%??,??????????????????90%??????
??:?????????????????
?? ???