问题 单项选择题

在下面的叙述中,属于TCP/IP协议特点的是
Ⅰ.开放的协议标准,独立于特定的计算机硬件与操作系统
Ⅱ.可以运行在局域网、广域网更适用于互联网
Ⅲ.整个TCP/IP设备在网络中具有唯一的IP地址
Ⅳ.可以提供多种可靠的用户服务

A.Ⅰ和Ⅱ

B.Ⅳ

C.Ⅲ

D.全部

答案

参考答案:D

解析: TCP/IP协议的特点有:开放的协议标准,独立于特定的计算机硬件与操作系统。可以运行在局域网、广域网,更适用于互联网。整个TCP/IP设备在网络中具有惟一的IP地址。可以提供多种可靠的用户服务。

阅读理解

阅读理解。

     Worrying about how you'll perform on a math test may actually contribute to a lower test score, US

researchers said on Saturday.

      Math anxiety-feelings of dread and fear and avoiding math-can weaken the brain's limited amount of

working capacity, a resource needed to calculate difficult math problems, said Mark Ashcrafi, a psychologist

at the University of Nevada Las Vegas who studies the problem.

     "It turns out that math anxiety occupies a person's working memory," said Ashcraft, who spoke at the

annual meeting of the American Association for the Advancement of Science in San Francisco.

     Ashcraft said while easy math tasks such as addition require only a small part of a person's working

memory, harder calculations require much more.

      Worrying about math takes up a large part of a person's working memory stores as well, spelling disaster

for the anxious student who is taking a high-stakes test ( 高风险测验).

     Stress about how one does on tests like college entrance exams can make even good math students choke.

"All of a sudden they start looking for the short cuts," said University of Chicago researcher Sian Beilock.

     Although test preparation classes can help students get over this anxiety, they are limited to students whose

families can afford them.

     Finally, she said, "It may not be wise to rely completely on scores to predict who will succeed."

     While the causes of math anxiety are unknown, Ashcraft said,"People who manage to get over math

anxiety have completely normal math ability."

1. Sian Beilock points out that stress________.

A. can't be avoided before college entrance exams

B. contributes to scores in college entrance exams

C. has no effects on good math students

D. has side effects on students in college entrance exams

2. What does the underlined word "spelling" probably mean?

A. causing

B. reducing

C. taking away

D. preparing for

3. What can we learn from the text?

A. The causes of math anxiety have already been found.

B. All of the students attend test preparation classes.

C. Math anxiety weakens working memory needed to do math.

D. Few measures can be taken to get rid of math anxiety.

4. What does the passage suggest middle school students do before exams?

A. Get relieved.

B. Review lessons.

C. Go to the doctor's.

D. Rely on scores.

问答题