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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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