每只日光灯的功率因数为0.5,若N只日光灯与N只白炽灯并联,则总功率因数（）。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='32632' and id < 2594816 and id<>'2594816' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='32632' and id > 2594816 and id<>'2594816' order by id asc limit 5