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举一反三
【单选题】The hotel was in a quiet street and seemed to agree with one who needed a good sleep after a tiring trip. The woman manager showed me to my room. When I asked her about dinner, she said it was served ...
A.
the rule for everyone was too strict
B.
C.
B. the manager asked me to go somewhere else
D.
E.
C. I hardly slept at all
【单选题】磨削表面有螺旋线的原因之一是，主要原因是砂轮圆周面上有凹凸现象，使磨削过程中砂轮与工件表面仅部分接触。砂轮修整不良或修整砂轮后未倒边角，此时可调整工作台在移动速度为（）的状态下重新修整砂轮，修后用白刚玉油石倒角。
A.
10～20mm/min
B.
30～50mm/min
C.
15～30mm/min
D.
20～40mm/min