题目内容
骨架空隙法结构具有()特性。
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某轴承厂有甲、乙、丙三个车间，各车间生产的轴承数量分别占全厂的40%、30%、 30%，各车间的次品率分别为3%、4%、5%(正品率分别为97%、96%、95%)。以上叙述如下图所示。
在图中，从“厂”结点出发选择三个车间产品的概率分别为0.4、0.3、0.3，从各“车间”结点出发选择“正品”或“次品”的概率如图所示。从“厂”结点出发，到达“正品”(或“次品”)结点，可以有多条路径。例如，路径“厂—甲一次品”表示该厂甲车间生产的次品，其概率P(厂一甲一次品)应等于各段上的概率之积。而该厂总的次品率应等于从“厂”结点到达“次品”结点的所有路径算出的概率之和(全概率公式)。而其中每条路径算出的概率在总概率中所占的比例，就是已知抽取产品结果再推测其来源(路径)的概率(逆概率公式)。根据以上描述，可以算出，该厂的正品率约为(53)。如果上级抽查取出了一个次品，那么该次品属于甲车间生产的概率约为(54)。
W: Congratulations! Does that mean you'll be moving soon？
Q: What do we learn about the man from the conversation？
(18)
Section A
Directions: In this section, you will hear 8 short conversations and 2 long conversations. At the end of each conversation, one or more questions will be asked about what was said. Both the conversation and the questions will be spoken only once. After each question there will be a pause. During the pause, you must read the four choices marked A, B, C and D, and decide which is the best answer.
听力原文：M: Oh my god! The heat is simply unbearable here. I wish we've gone to the beach instead.
W: Well, with the museums and restaurants in Washington, I'll be happy here no matter what the temperature.
Q: What does the woman mean？
(12)
箱涵顶进作业应在地下水位降至基底以下()m后进行。
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