频率属于超声频率的是（     ）

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SQL Error: select id,body,options from ***_enewstiku where sourceid='25746' and id < 2163641 and id<>'2163641' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='25746' and id > 2163641 and id<>'2163641' order by id asc limit 5