导墙施工的检验标准
| The discovery of planets around distant
stars has become like space-shuttle launches — newsworthy but just barely. With
some 50 extra solar planets under their belt, astronomers have to announce
something really strange to get anyone’s attention. Last week they did just that. Standing in front of colleagues and reporters at the American Astronomical Society’s semiannual meeting in San Diego, the world’s premier planet-hunting team — astronomer Geoffrey Marcy of the University of California, Berkeley, and his colleagues — presented not one but two remarkable finds. The first is a pair of planets, each about the mass of Jupiter, which whirl around their home star 15 light-years from Earth in perfect lockstep. One takes 30 days to complete an orbit, the other exactly twice as long. Nobody has ever seen s A. New Planetary Puzzlers B. "Hot Jupiters" Challenging Conventional Theory C. A Redefinition of "Planet" D. Two Remarkable Finds [简答题]为什么要保护环境？
[判断题]《高速铁路铁路技术管理规程》规定：路基面的宽度，应考虑设计速度、轨道类型、线间距、电缆槽、接触网支柱、路肩宽度等计算确定。
A.正确 B.错误 [单项选择]病理诊断肉瘤的主要依据是（）。
A. 间质稀少 B. 血液供应丰富 C. 有肺转移 D. 瘤细胞呈弥散分布 E. 浸润性生长 [单项选择]加催化剂可使化学反应的下列哪个物理量发生改变？（）。
A. 反应热 B. 平衡常数 C. 反应熵变 D. 速率常数 [多选题]消防员佩戴空气呼吸器可使其呼吸器官免受( )的伤害。
A.浓烟 B.毒气 C.高温 D.缺氧 [单选题]“3.16”人身事故，丰宁抽蓄电站灌浆施工作业发生1死1伤，事故教训之一为（）不得独立承担危险性较大的分部分项工程。
A.专业分包人员 B.业务外包人员 C.劳务分包人员 D.特种作业人员 [单选题](76682)为使低碳钢便于切削加工,应采用()热处理。(1.0分)
A.完全退火 B.球化退火 C.正火 D.回火 我来回答: 提交
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