电流的计量单位是()。 ["A、伏特;","B、焦耳;","C、安培;","D、瓦特"]
电荷定向流动称为()。 ["A、电势","B、电压","C、电流","D、电源"]
心包积液时可见到()二尖瓣狭窄可见到() ["靴形心","梨形心","烧瓶状心","心尖部矛盾运动","心浊音界明显缩小"]
低压配电线路一般应装设()。 ["A、过载保护","B、短路保护","C、失压保护","D、热保护"]
船政学堂中的()是负责教授航海教程、管轮操作的。 ["A、左学堂","B、右学堂","C、前学堂","D、后学堂"]
二尖瓣狭窄的舒张期杂音()主动脉瓣关闭不全的舒张期杂音()