()是经济型数控机床按驱动和定位方式划分。
A、闭环连续控制式
B、变极控制式
C、步进电动机式
D、直流点位式
参考答案:C
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- _____. Few of them are your real friends.
A.That’s not the case
B.That’s for sure
C.I couldn’t agree more
D.I’m pleased to know that
蘑菇是生态系统中的生产者。 [ ]