碳钢和铸铁的含碳量分界值是0.77%。 （ ）

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SQL Error: select id,body,options from ***_enewstiku where sourceid='24888' and id < 2124261 and id<>'2124261' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='24888' and id > 2124261 and id<>'2124261' order by id asc limit 5