执行下面程序段,屏幕上将输出( )。 public class Test pri

题型:单项选择题

问题:

执行下面程序段,屏幕上将输出( )。
public class Test
private int x=10,y=20;
public Test (int x,int y)
System.out.println (x+this.x);
System.out.println (y+y);
public static void main (String[] args)
Testt= new Test(30,50);

A.无输出

B.20
40

C.40
100

D.40
70

考点:计算机等级考试JAVA二级JAVA笔试
题型:单项选择题

Do you think there is too much noise in our city? If you live near an airport,you will be unhappy because of a plane often make a loud noise.The sound of planes or heavy vehicles is likely to cause deafness if heard continuously(不断地).

However, most people in our city do not seem to mind noise. They like to enjoy music when they are doing uninteresting jobs.It is a new danger because pop music,when played through powerful amplifiers(放大器),can reach 120 decibels(120分贝的)at a distance of five feet.A continuous noise of over 85 decibels can cause deafness.It was discovered that many young people in America could hear no better than 65-year-old people.

In the past we used to think that only workers in very noisy places would become deaf.For example,when newspapers and books are being printed,the noise level is over 85 decibels,and some of the workers become deaf.Today,however,scientists believe that 10 percent of the workers in Britain are being deafened by the noise.

Sometimes noise of less than 85 decibels can make some people tired and stressed.We all know that too much noise makes life difficult and unpleasant.It can do great harm to people's health and prevent people from working well.Workers in noisy offices are not as efficient(效率高的)as those in quiet offices.Noise makes people less efficient.Can anything be done to reduce or control noise?

In Britain the government has made several laws to reduce noise.Though the government has spent a lot of money in making airports and main roads quieter,many people think that there are still not enough laws.For example,there are no laws to control the noise of machines.In Japan,America and Norway there are such laws.As a result,workers can be given compensation(赔偿)if they become deaf.

小题1:Some workers become deaf because of ________.

A.hard work

B.a continuous noise of over 85 decibels

C.powerful amplifiers

D.uninteresting jobs小题2:In Britain there are laws to ________.

A.stop workers from becoming deaf

B.control the noise of machines

C.keep down noise

D.help deaf workers in need小题3:Who can be given compensation if they become deaf?

A.American workers.

B.British workers.

C.Both American workers and British workers.

D.None of the above answers.

题型:单项选择题

2012年6月16日,在海阳亚沙会开幕式上,沙特阿拉伯旗手高举的国旗上写着“万物非主,唯有真主,穆罕默德是安拉的使者。”这表明该国的国教是

A.佛教

B.基督教

C.伊斯兰教

D.道教

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下列关于石灰的说法错误的是:

A.生石灰通常可以作为食品干燥剂 

B.澄清石灰水放置在空气中易变浑浊 

C.汉白玉与石灰石的主要成分相同 

D.“烈火焚烧若等闲”指高温煅烧

题型:单项选择题

世界卫生组织推荐的药物敏感试验方法为()法。

题型:单项选择题

在地面上,行走是指用双腿克服地球引力,轮流迈步,从一处地面走向另一处地面。太空行走是指在太空轨道飞行的失重环境中行走,失重将行走的概念完全搞乱了。在航天器密封座舱中行走,只要用脚、手或身体任何部位触一下舱壁或任何固定的物体,借助反作用力,就可以飘飞到任何想去的地方。座舱里充满空气,划动四肢也可前进,因此行走范围是立体的。

随着航天事业的发展,有大量工作需要航天员走出密封座舱,这是一件非常困难的事。太空是高真空、强辐射和极端温度环境,还有微流星体伤害,必须身着舱外活动航天服以保证生命安全,但也不能立即走出密封座舱,因为还要吸纯氧排氮。由于氧气助燃,容易引起火灾,所以密封座舱中一般不用纯氧,而用以氧、氮为主的混合气体。这样,航天员体内便存在大量的氮。这些氮不像氧和二氧化碳那样会与血红蛋白和缓冲物质起化学作用,而是物理地溶解在血液和脂肪组织中。目前,密封座舱中一般采用与地面相同的1个大气压,即760毫米汞柱,而舱外活动航天服一般采用210毫米汞柱压力。这样,穿上航天服后,体外压力降低,溶解在脂肪组织中的氮便游离出来。由于脂肪组织中的血液供应较差,流动量不大,不能将氮气迅速地通过血液带到肺部排出,因而会在血管内外形成气泡,堵塞血管,形成气胸。这就是减压病。为了防止减压病,必须在出舱前吸纯氧,使体内的氮气逐渐排出。

当然,太空行走不仅仅是在太空轨道飞行时的行走,还包括在其他天体上的行走。比如在月球上行走。由于月球表面没有空气,因而没有空气阻力,加上重力只有地球重力的1/6,如果像在地球上那样双脚轮流迈步,走起来会轻飘飘的,一蹬地身体就会弹得老高,一步能跨出老远,感觉很别扭,还不如像袋鼠一样双脚并齐、向前蹦跳感到舒适。

什么是太空行走()

A.在太空里飞行

B.在密封座舱外靠太空机动器来移动身体

C.在木星等天体上行走

D.在太空轨道飞行的失重环境中或在其他天体上行走

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