一个100mH的电感元件,接在u=141sin(314t+60°)V的交流电源上,该电感元件的感抗值为()欧。
A、20
B、31.4
C、62.8
D、100
参考答案:B
B细胞不具备的受体
A.mIg受体B.有丝分裂素受体C.C3b受体D.Fc受体E.E受体
The rich only ____ themselves in making money and had no eye for the needs and welfare
of their workers. [ ]
A. devoted
B. occupied
C. enjoyed
D. concerned