精密模具的精度一般应该达到()。
A.0.5~1mm
B.0.1~0.56mm
C.0.05~0.1mm
D.0.005~0.01mm
参考答案:D
Look! ________ an eraser. [ ]
A. This's
B. It's
C. What's
D. That
为什么电机车集电弓必须起落灵活?