试题与答案

在UNIX系统中,______用于把一个进程的输出连接到另一个进程的输入。A) 普通

题型:单项选择题

题目:

在UNIX系统中,______用于把一个进程的输出连接到另一个进程的输入。

A) 普通文件
B) 特殊文件
C) 目录文件
D) 管道文件

答案:

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题型:阅读理解
Nowadays, too much carbon dioxide makes the earth warmer and warmer and causes terrible effect to human beings. To save our planet and ourselves, a new lifestyle called low-carbon life becomes popular. Low carbon means low energy and no waste. It is necessary for everybody to learn to live a low-carbon life.
To live a low-carbon life, we’d better save energy as much as possible. Turn off the lights and TV whenever they are not needed. If possible, use cold water to wash clothes or dishes. Take a short shower and try to take a cold one when the weather gets warm. Don’t do the cooking with electricity.
To live a low-carbon life, we should eat less meat. Everybody knows eating too much meat makes people fat and easy to have heart disease, but maybe you don’t know keeping animals for food produces even more carbon dioxide than all the cars in the world, and being a vegetarian (素食主义者) can help reduce one and a half tons of carbon dioxide a year. Maybe it is a little difficult, but it’s really necessary.
To live a low-carbon life, we are supposed to do less shopping. When we go shopping, we may drive a car or take other transportations (交通工具). On one hand, these machines pollute the air and waste energy. On the other hand, most of us always buy some useless things because of some advertisements. It not only waste money but also causes trouble to the earth, because making everything will produce carbon dioxide more or less.
There are many other ways to live a low-carbon life, such as recycling things, planting trees and reusing textbooks. If we can keep it a habit in our daily life, the earth will become a safer planet for us to live on.
任务一:根据短文内容,用简洁的句子或短语完成下列表格。
Advice
How to Live a Low-Carbon Life
Advice 1
﹡ 1.                                                                    
Advice 2
﹡ 2.                                                                    
Advice 3
﹡ Take a short shower and try to take a cold one when it’s warm.
Advice 4
﹡ 3.                                                                    
Advice 5
﹡ 4.                                                                    
Advice 6
﹡ Be supposed to do less shopping.
Advice 7
﹡ Recycle things, plant trees and reuse textbooks.
任务二:除了文中提到的建议外,你一定还有许多自己的想法,请写一条与大家分享吧。
﹡ 5.                                                                                    
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题型:问答题

在学习了金属的性质后,化学实验小组同学对“21世纪的重要金属材料钛和钛合金”产生了兴趣,他们进行了如下探究,并请你一同参与。

查阅资料:

(1)钛的硬度与钢铁差不多,而它的质量只有同体积钢铁的一半,钛虽然稍比铝重一点,可它的硬度却比铝大两倍。

(2)钛属于化学性质比较活泼的金属,但在常温下钛的抗腐蚀性很强。有人曾把一块钛沉到海底,五年以后取上来,发现一点锈也没有生,依旧是亮光闪闪。

(3)钛具有“亲生物”性,在人体内能抵抗分泌物的腐蚀且无毒。

活动与探究:

(1)钛与铁的金属活动性哪一种强?

【提出假设】:                                             。

【设计实验】:                                              。

若钛的活动性比铁强,以上实验出现的现象是:                    。

(2)钛是比较活泼的金属,为什么耐腐蚀性却很强?

可能的原因是:                                       。

(3)你想探究的问题是:                                。

思考与应用:“物质的性质一定程度上决定它的用途”请判断钛有哪些用途?(要求两条)

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