A.1 B.3 C.5 D.7
A.按下電源按鈕“B” B.按下檢流計(jì)按鈕“G” C.松開(kāi)電源按鈕“B” D.松開(kāi)檢流計(jì)按鈕“G”
A.0 B.∞ C.0.1 D.0.01