车削多线螺纹时,轴向分线时应按()分线。A、螺距 B、导程 C、头数 D、角度

题型:单项选择题

问题:

车削多线螺纹时,轴向分线时应按()分线。

A、螺距

B、导程

C、头数

D、角度

考点:数控车床工考试数控车床工考试题库
题型:单项选择题

2006年2月10日,中国航天局将如图所示的标志确定为中国月球探测工程形象标志。它以中国书法的笔触,抽象地勾勒出一轮明月,一双脚印踏在其上,象征着月球探测的终极梦想.假想人类不断向月球“移民”,经过较长时间后,月球和地球仍可视为均匀球体,地球的总质量仍大于月球的总质量,月球仍按原轨道运行,以下说法正确的是(   )

A.月球之间的万有引力将变小

B.月球绕地球运行的周期将变大

C.月球绕地球运行的向心力加速度将变小

D.月球表面的重力加速度将变大

题型:单项选择题

世界人口达到60亿的时间是()

A.2000年5月

B.2020年1月

C.1998年12月

D.1999年10月12日

题型:单项选择题

A点高程230.000m,B点高程236.500m,下列说法中的()是正确的。

A.B点比A点高

B.A点比B点高

C.A-B的高差是6.500m

D.A-B的高差是-6.500m

E.A点到B点的坡度是6.5%

题型:单项选择题

建设工程设计合同示范文本中,发包人委托的设计任务可以包括( )。

A.项目建议书

B.初步设计

C.技术设计

D.产品设计

E.施工图设计

题型:单项选择题

There is a difference between science and technology. Science is a method of answering (1) questions; technology is a method of solving practical problems. Science has to do with discovering the facts and relationships between (2) phenomena in nature and with establishing theories that (3) to organize these facts and relationships; technology has to do with tools, techniques, and (3) for applying the findings of science. Another (5) between science and technology has to do with the progress in each.

Progress in science (6) the human factor. Scientists, who seek to understand the universe and know the truth within the highest degree of (7) and certainty, cannot (8) their own or other people’s likes or dislikes or to popular ideas about the fitness of things. What scientists discover may shock or (9) people-as did Darwin’s theory of evolution. But even an unpleasant truth is (10) than likely to be useful; besides, we have the choice of refusing to believe it! But (11) so with technology; we do not have the choice of refusing to hear the sound produced by a supersonic aircraft flying overhead; we cannot refuse to breathe polluted air. (12) science, progress in technology must be measured (13) the human factor. The purpose of technology is to serve people—people (14) , not merely some people; and future generations, not merely those who presently wish to (15) advantage for themselves.

We are all familiar with the (16) use of technology. Many people blame technology itself (17) widespread pollution, resource depletion (枯竭) and even social decay in general—so much (18) the promise of technology is " (19) " That promise is a cleaner and healthier world. If wise applications of science and technology do not (20) a better world, what else will

6()

A.distracts

B.excludes

C.expels

D.disposes

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