关于机械能守恒，下列说法正确的是（      ） 

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='17521' and id < 1482918 and id<>'1482918' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='17521' and id > 1482918 and id<>'1482918' order by id asc limit 5