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问题 选择题

下列关于燃烧现象的描述，正确的是（　　）

A．红磷在空气中燃烧产生大量的白雾

B．氢气在空气中燃烧发出淡蓝色火焰

C．镁条在空气中燃烧生成氧化镁

D．铁丝在空气中剧烈燃烧，火星四射

答案

A、红磷在空气中燃烧，产生大量的白烟，而不是白雾，故选项说法错误．

B、氢气在空气中燃烧，发出淡蓝色火焰，故选项说法正确．

C、镁条在空气中燃烧，发出耀眼的白光，生成一种白色固体；生成氧化镁是实验结论而不是实验现象；故现象说法错误．

D、铁丝在空气中只能烧至发红，不会产生火星，故选项说法错误．

故选B．

单项选择题

制定城市、镇控制性详细规划的基本程序的正确顺序是( )
①城市人民政府城乡规划主管部门和县人民政府城乡主管部门，镇人民政府根据城市和镇的总体规划，组织编制控制性详细规划，确定规划编制的内容和要求等；②规划方案的修改完善；③城市详细规划编制中，应当采取公示、征询等方式，充分听取规划涉及的单位，公众的意见。对有关意见采纳结果应当公布；④组织编制机关及时公布经依法批准的城市和镇控制性详细规划。同时报本级人民代表大会常务委员会和上一级人民政府备案；⑤组织编制机关将规划草案予以公告，并采取论证会、听证会或者其他方式征求专家和公众的意见，公告时间不得少于30日；⑥组织编制机关委托具有相应资质等级的单位承担具体编制工作；⑦规划方案报请审批

A．①⑥⑤③②⑦④
B．①⑥②③⑤④⑦
C．⑥①③②⑤⑦④
D．①⑥③⑤②⑦④
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单项选择题

It should go without saying that the focus of UML is modeling. However, what that means, exactly, can be an open-ended question. (71) is a means to capture ideas, relationships, decisions, and requirements in a well-defined notation that can be applied to many different domains. Modeling not only means different things to different people, but also it can use different pieces of UML depending on what you are trying to convey. In general, a UML model is made up of one or more (72) . A diagram graphically represents things, and the relationships between these things. These (73) can be representations of real-world objects, pure software constructs, or a description of the behavior of some other objects. It is common for an individual thing to show up on multiple diagrams; each diagram represents a particular interest, or view, of the thing being modeled. UML 2.0 divides diagrams into two categories: structural diagrams and behavioral diagrams. (74) are u sed to capture the physical organization of the things in your system, i.e., how one object relates to another. (75) focus on the behavior of elements in a system. For example, you can use behavioral diagrams to capture requirements, operations, and internal state changes for elements.

A. things B. picturesC. languages D. diagrams
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