方差的平方是标准差。（）[2009年5月三级真题]

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SQL Error: select id,body,options from ***_enewstiku where sourceid='25282' and id < 2138995 and id<>'2138995' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='25282' and id > 2138995 and id<>'2138995' order by id asc limit 5