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问题 填空题

如图所示，两个紧压的铅柱结合起来了，并能吊起一定的重物。该实验现象表明：紧压的两铅柱分子之间存在             。

答案

引力

题目分析：分子动理论的内容是：物质是由分子组成的，分子在不停地做无规则的运动，分子间存在相互作用的引力和斥力。如图所示，两个紧压的铅柱结合起来了，并能吊起一定的重物。该现象表明分子间存在引力。

单项选择题

改变主要通风机转速或风机叶片安装角必须经（）批准。

A、矿长

B、总工程师（技术负责人）

C、业主
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单项选择题

The analysis phase answers the questions of who will use the system，what the system will do，and where and when it will be used．During this phase，the project team investigates any current system，identifies （），and develops a concept for the new system．This phase has three steps：first，（） is developed to guide the project team’s efforts．It usually includes an analysis of the current system and its problems，and the ways to design a new system．The next step is （）．The analysis of this information-in conjunction with input from the project sponsor and many other people-leads to the development of a concept for a new system．The system concept is then used as a basis to develop a set of business analysis models that describes how the business will operate if the new system were developed．The set of models typically includes models that represent the  （） necessary to suppor the underlying business process．Last，the analyses，system concepts，and models are combinedin to a document called the （），which is presented to the project sponsor and other key decision makers that decide whether the project should continue to move forward．

Last，the analyses，system concepts，and models are combinedin to a document called the （），which is presented to the project sponsor and other key decision makers that decide whether the project should continue to move forward．

A．requirements statement

B．design specification

C．system proposal

D．project charter
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