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参考解析：
刷刷题刷刷变学霸
举一反三
【单选题】Passage 3 Questions 11 to 15 are based on the following passage: Scientists in India have invented a new way to produce electricity. Their invention does not get its power from oil, coal or other fuel...
A.
Because bullocks have long been used by Indian people
B.
Because bullocks walk slowly and are easy to control.
C.
Because there are few non-working bullocks in India
D.
Because there is not enough oil in India.
【单选题】下面是关于超精密磨削时工件纵向进给量的描述，错误的是（）。
A.
工件纵向进给量直接影响工件表面粗糙度
B.
当增大纵向进给量时，工件表面不易产生螺旋形刀痕
C.
为进一步细化工件表面粗糙度，可适当增加磨削次数
D.
当增大纵向进给量时，磨削力和磨削热也随之增大