液压传动与电气及机械传动相比不易实现大范围的无极调速。（）
参考答案：错
There was still the possibility that Lake Tanganyika and not Lake Victoria was the true ______ of the Nile.[ ]
A. source
B. resource
C. cause
D. course
铸钢侧架导框内侧面磨耗（含局部磨耗）深度大于（）时，堆焊后加工。
A、lmm
B、1.5mm
C、2mm
D、3mm
