应用简易呼吸器时，每次挤压的空气量和挤压的频率分别是（ ）。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='30905' and id < 2486674 and id<>'2486674' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='30905' and id > 2486674 and id<>'2486674' order by id asc limit 5