A.76% B.74% C.69%
A.并联 B.先并联后串联 C.串联
A.使之躺下,把腿垫高,使血液回流 B.适当保暖,以防受凉 C.松开衣领腰带,使之呼吸畅通 D.使中毒者吸氧气
A.5% B.7% C.10%
A.O2 B.CO C.CO2
A.生焦 B.过火 C.成熟
A.大丝杆断 B.机头轴断 C.电机烧坏