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??????????2?17? (???? ??)????????17?,???????????,2??????????13?????????????????16?,???????????,????????72????????????15.3?,?????????;???????????????????10???48???????6.5?~10.9????,??;?????????????????????????????????4???
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?????2???????18???2????????????????????22???,?????,??????????????,??????????2???19???????2??????20?,?,????????????,???????????,????????????????,???(???????????)
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