【单选题】. Going on a trip to a far-away destination _________ be expensive and difficult, but it is very interesting.
【单选题】共集电极放大器的输入电阻 ,输出电阻 。
【单选题】与共射单管放大电路相比,射极输出器(共集)电路的特点是 ( )。
【简答题】完形填空 My husband has been ill in hospital for two months and I have learned to make do with very little (凑合过日子). One Sunday afternoon, I went to buy a 1 for my daughter with my friend. A woman who was...