为了提高放大器的输入电阻、减小输出电阻，应该采用电压串联负反馈。()
555定时器组成的单稳态触发器是在TR端加入负脉冲触发的。()
运算放大器组成的反相比例放大电路，其反相输入端与同相输入端的电位近似相等。()
People today are more likely to admire______.
A. politicians
B. those who start their own company
C. people in their 20s and 30s
D. Fortune 500 CEOs
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