110V和220V直流系统的电源应采用( )。
A.自耦式互感电源
B.三相中性电源
C.蓄电池组
D.电力用直流电源变换器
参考答案:C
从A、B、C、D四个选项中,选出与所给句子划线部分意义相同或相近的一项。
—It's raining these days. I won't ride my bike to school tomorrow. —I won't, either. [ ]
A. So won't I
B. So I won't
C. Neither will I
D. Neither I will
人字闸门在安装检修时可利用顶枢调整门叶旋转轴位置,使轴线保持水平。()