尿素装置高压洗涤器系统调温水的进口温度不得低于130℃，高压洗涤器的液体出口应设（）。
A.高温报警
B.低温报警
C.高低温报警
参考答案：B
—If you have any trouble, be sure to call me.
—_______.
A．I am glad to hear that
B．I will. thank you very much.
C．I have no trouble
D．I will think it over
某电路的电阻增加了4欧电流降为原来的一半，若电源电压不变，那么原来电路中的电阻是______欧，增加电阻后原电阻上消耗的功率之比是______．
