在真空中传播的所有电磁波均具有相同的量是（  ）

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SQL Error: select id,body,options from ***_enewstiku_ where sourceid='8729' and id < 708240 and id<>'708240' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku_ where sourceid='8729' and id > 708240 and id<>'708240' order by id asc limit 5