鼻石是（）。 A.鼻腔内外源性的石头异物 B.鼻腔内异物被肉芽组织所包裹而形成 C.

Scientists from the Max Plank Institute for Biological Cybernetics in Tubingen, Germany, have presented the first experimental evidence that people do end up walking in circles if lost in unfamiliar areas．The study, published in the journal Current Biology, examined the tracks of people who walked for several hours in the Sahara desert in Tunisia and in the Bienwald forest in Germany．Researchers Jan Souman and Marc Ernst said the scientists used the global positioning system （GPS） to record these paths．The results showed that the walkers were only able to keep a straight line when the sun or moon was visible．As soon as the sun disappeared behind some clouds, people started to walk in circles without even noticing it．

Souman said one explanation offered in the past for people walking in circles was that most people have one leg longer or stronger than the other, which would produce a systematic bias（偏差） in one direction．To test this．the researchers asked people to walk straight while blindfolded which removed the effects of vision．They found that these circles were rarely in a systematic direction, with the same person sometimes switching to the left and sometimes to the right．

"Most of the participants in the study walked in circles, sometimes in extremely small ones．Walking in circles is therefore not caused by differences in leg length or strength, but more likely the result of increasing uncertainty about where straight ahead is," said Souman, "Small random errors （随机性误差） in the various sensory signals that provide information about walking direction add up over time, making what a person perceives to be straight ahead drift away from the true straight ahead direction．"

72．The underlined word "this" in Paragraph 2 refers to _____．

A．the effects of vision             B．a systematic bias

C．the leg length differences         D．one explanation offered in the past

73．What is the probable reason for people's walking in circles?

A．The invisible sun or moon．

B．The increasing uncertainty about directions．

C．Differences in leg length or strength．

D．Wrong signals providing information about areas．

74．Why are the subjects required to be blindfolded?

A．To encourage them to walk straight．    B．To stop them from seeing each other．

C．To dismiss the effects of vision． D．To keep the test a top secret．

75．Which of the following statements is true?

A．People walk straight in the day．

B．The farther people walk, the greater the direction bias grows．

C．People walk only in large circles．

D．Researchers use the global positioning system to record their tracks．

以下选项中不属于教学设计理论基础的是（）。

A.教学理论

B.传播理论

C.学习理论

D.计算机理论

下列哪项是加剧肾小球硬化的主要因素（）

A.三高现象

B.补体

C.血小板

D.中性粒细胞

E.内皮细胞

信息是有层次的，最有效用的信息是知识和（）

A.智能

B.迹象

C.决策

D.事实

(每小题只有一个正确答案，请从每小题的备选答案中选出一个你认为正确的答案)

下列选项中，属于关联关系对独立性造成影响的是( )。

A．与甲公司存在密切的经营关系

B．鉴证小组成员C曾是鉴证客户的经理

C．甲公司的董事曾是会计师事务所的前高级管理人员

D．鉴证小组成员D可能与甲公司发生雇佣关系