A.基極階梯信號(hào)和集電極掃描信號(hào)的極性開(kāi)關(guān)都撥向“+”
B.基極階梯信號(hào)和集電極掃描信號(hào)的極性開(kāi)關(guān)都撥向“-”
C.基極階梯信號(hào)極性開(kāi)關(guān)撥向“+”，集電極掃描信號(hào)撥向“-”
D.基極階梯信號(hào)極性開(kāi)關(guān)撥向“-”，集電極掃描信號(hào)撥向“+”

A.浸油潤(rùn)滑
B.滴油潤(rùn)滑
C.噴霧潤(rùn)滑
D.潤(rùn)滑脂