选择题：下列物品中，通常属于导体的是 A．塑料布 B．玻璃板 C．食盐水 D．空气

题型：完形填空

Directions：For each blank in the following passage there are four words or phrases marked A，B，C and D．Fill each blank with a word or phrase that best fits the context．
In the past, man didn’t have to think about the protection of his environment. There were few people on the earth, and natural resources seemed to be 36  .
Today things are 37 , and the world has become too 38 . We’re using up our natural resources too quickly, and at the same time we are  39  our environment with dangerous chemicals. If we continue to do this, human life on the earth will not survive.
Everyone 40   today that if too many fish are taken from the sea, there will soon be none left. Yet, with modern fishing 41  , more and more fish are caught. We know that if too many trees are cut down, forests will disappear and nothing will grow on the land. Yet, we   42 to use bigger and more powerful machines to cut down more and more trees.
We know that if rivers are polluted with waste products from factories, we’ll die. 43 , in most countries wastes are still put into rivers or into the sea, and there are 44   laws to stop this.
We know, too, that if the 45   of the world continues to rise at the present rate, in a few years there will not be enough food . What can we do to solve these problems?
If we eat more vegetables and less meat there will be more food available for every one. Land that is used to grow crops   46  five times more people than land where animals are kept. Our natural resources will last longer if we learn to recycle them.
The world population will not rise so quickly if people use modern methods of birth control.
Finally, if we educate people to think about the problems, we shall have a better and cleaner 47   in the future.

小题1:

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题型：推断题

Q、R、X、Y、Z五种元索的原子序数依次递增。

已知：

①Z的原子序数为26，其余的均为短周期主族元素；

②Y原子价电子（外围电子）排布msⁿmpⁿ；

③R原子核外L层电子数为奇数；

④Q、X原子p轨道的电子数分别为2和4。

请回答下列问题：

(1)Z元素的基态原子核外电子排布式是___________________。

(2)Q与Y形成的最简单气态氢化物分别为甲、乙，下列判断正确的是___________。

a．稳定性：甲>乙，沸点：甲>乙

b．稳定性：甲>乙，沸点：甲<乙

c．稳定性：甲<乙，沸点：甲<乙

d．稳定性：甲<乙，沸点：甲>乙

(3)Q、R、X三种元素的第一电离能数值由小到大的顺序为___________（用元素符号作答）。

(4)Q的一种氢化物相对分子质量为26，其中分子中的σ键与π键的键数之比为__________________

(5)五种元素中，电负性最大与最小的两种非金属元素形成的晶体类型是______________

(6)Z有δ、γ、α三种同素异形体，γ晶体晶胞中所含有的Z原子数为____________，δ、α两种晶胞中Z原子的配位数之比为______________。

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题型：单项选择题

对于二元函数z=f（x，y），下列结论正确的是（）。

A．A

B．B

C．C

D．D

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题型：单项选择题

供气消防车应加装了冷冻干燥装置，保持压缩空气的温度，达到的规定值为（）℃

A.35.0

B.40.0

C.45.0

D.50.0

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题型：填空题案例分析题

图1表示人体内某些淋巴细胞的分化，图2表示免疫过程，X表示抗原，数字表示过程，m、n代表场所，其余字母表示细胞或物质。请分析回答下列问题：

为检测某疫苗是否有效，研究人员设计了如下实验方案：

第一步：将某种（）健康动物若干只，平均分成对照组和实验组。

第二步：对照组接种不含疫苗的接种物，一段时间后再接种病毒；实验组接种含疫苗的接种物，（）第三步：统计实验组和对照组动物的发病率、存活率。若与对照组相比，实验组动物发病率低、存活率高，则可以判断该疫苗有效。产生这一结果的原因是（）（填图1中数字）过程是实验组动物所特有的。

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下列物品中，通常属于导体的是 A．塑料布 B．玻璃板 C．食盐水 D．空气

题目：

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