____是板料从2~4根同步旋转的辊轴间通过，并连续产生塑性弯曲的一种成形方法。
查看答案
等曲率圆筒形件滚弯时，3个滚轴的位置需要倾斜一定的角度。
A. 对
B. 错
滚弯成形是连续产生塑性弯曲的一种成形方法度。
A. 对
B. 错
What does the speaker say about animals in winter?[音频]
A. They have to look for food and shelter underground.
B. They take little notice of the changes in temperature.
C. They resort to different means to survive the bitter cold.
D. They have difficulty adapting to the changed environment.
Wha do we learn about animals that sleep through winter?
A. They have their weight reduced to minimum.
B. They consume energy stored before the long sleep.
C. They can maintain their heart beat at the normal rate.
D. They can keep their body temperature warm and stable.
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