振动源向着接收体运动时，接收频率的变 化是（     ）

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SQL Error: select id,body,options from ***_enewstiku where sourceid='25728' and id < 2162949 and id<>'2162949' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='25728' and id > 2162949 and id<>'2162949' order by id asc limit 5