A.20% B.30% C.50% D.60%
A.15% B.25% C.35% D.45%
A.800MΩ B.1000MΩ C.1500MΩ D.2000MΩ
A.用鉛絲將二次短接 B.用導(dǎo)線纏繞短接二次 C.用短路片將二次短接 D.將二次引線拆下
A.插座箱 B.插座 C.插座盒 D.插座頭
A.200mm B.250mm C.300mm D.400mm
A.頭部前傾 B.頭部后仰 C.頭部墊高 D.吹氣力度不當(dāng)
A.2.5m B.3.0m C.3.5m D.4.0m
A.20% B.25% C.30% D.35%