检查氯化物杂质,应用的酸性溶剂是()
A.盐酸
B.硫酸
C.硝酸
D.磷酸
E.乙酸
参考答案:C
It's your choice! ____ she leaves ____ I will! [ ]
A. Neither; nor
B. Either; or
C. Both; and
D. Not only; but also
简述三相交流换向器电机调速的原理。