需求的价格弹性等于（ ）。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='31437' and id < 2520160 and id<>'2520160' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='31437' and id > 2520160 and id<>'2520160' order by id asc limit 5