渔民依靠声呐探测鱼群，利用了回声现象。 （ ）

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SQL Error: select id,body,options from ***_enewstiku where sourceid='29893' and id < 2424908 and id<>'2424908' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='29893' and id > 2424908 and id<>'2424908' order by id asc limit 5