某建筑内共安装使用了点型光电感烟火灾探测器200只，点型感温火灾探测器600只，则总共至少应有（ ）只备品。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='29273' and id < 2383614 and id<>'2383614' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='29273' and id > 2383614 and id<>'2383614' order by id asc limit 5