如通过两电灯的电流I分别为5A和6A,其两端电压U同为12V,则这两电灯的功率P分别为()。
参考答案:60J/s 72J/s
—Do you know our school at all?
—No, this is the first time I ________ here.
A.was
B.have been
C.came
D.am coming
扩散氢含氢量测定的目的是什么?