集成运算放大器输入级一般采用差动放大电路，其目的是要获得很高的电压放大倍数。
参考答案：错
After ______ seemed hours of waiting in line, finally it was our turn to pass the gateway.
A．that
B．it
C．what
D．which
货主企业的运营成本和费用是物流企业物流成本的转移。
