?? ???????????2????????6??18??:
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??????:
1??;
2?????????????????;
3?????????;
4??????????????????????
??:?????????
???100?????3???????
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??2?????????0.4%
??1???2?!??????????????
???:??????????????????
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??:??????????????????
???????\"???\"??9???????
????:????10???????????????…
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CBA?????????????????
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?????20????????????????
??2?????????0.4%
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???:??????????????????
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????:????????10?20?8
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GIF-??????????????????