脲酶活性最强的细菌是()
A.变形杆菌
B.流感嗜血杆菌
C.幽门螺杆菌
D.布鲁菌
E.流感嗜血杆菌
参考答案:C
一_____ do you water the plants?
— Twice a day. [ ]
A. How long
B. How soon
C. How often
D. How much
A.副线圈输出交流电的频率为10Hz
B.交流电压表的示数为20V
C.电阻R上消耗的电功率为2kW
D.原线圈中电流的最大值为100A