为保证槽底精度,切槽刀主刀刃必须与工件轴线()
A.平行
B.垂直
C.相交
D.倾斜
参考答案:A
For many seniors in some universities, the final year can be an unpleasant experience, _______ that ends the campus romance.
A.which
B.the one
C.what
D.one
垄断厂商利润极大时()。
A.P=MR=MC
B.P>MR=MC
C.P>MR=MC
D.P>MC=AC