从滚珠返回的灵活性及丝杠装配、预紧调整的方便性方面考虑,数控机床应该采用()结构。
A.内循环式单螺母
B.内循环式双螺母
C.外循环式单螺母
D.外循环式双螺母
参考答案:B
组成人体的最基本结构层次是指( )
A.细胞
B.组织
C.器官
D.系统
Which real estate valuation approach is most likely to require specific information about an investor to estimate the value of a property()
A. Cost approach.
B. Income approach.
C. Discounted after-tax cash flow approach.