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问题 选择题

如图所示，红蜡块能在玻璃管的水中匀速上升，若红蜡块在 A点匀速上升的同时，使玻璃管水平向右作匀加速直线运动，则红蜡块实际运动的轨迹是图中的（     ）

A．直线P

B．曲线Q

C．曲线R

D．无法确定

答案

答案：B

题目分析：两个分运动的合加速度方向水平向右，与合速度的方向不在同一条直线上，所以合运动为曲线运动，根据曲线运动的合力（加速度）大致指向轨迹凹点的一向，知该轨迹为曲线Q．故B正确，A、C、D错误．

故选B．

点评：解决本题的关键掌握判断直线运动还是曲线运动的方法，当速度方向与合力方向在同一条直线上，做直线运动，当合力方向与速度方向不在同一条直线上，做曲线运动．

单项选择题

以下哪个地址是Ethernet的物理地址________。

A．10.254.1.220

B．00-60-08-00-A6-38

C．10-65-08

D．:::10.0.0.1
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完形填空

读写任务（共1小题，满分25分）

阅读下面的短文，然后按照要求写一篇150词左右的英语短文

This is a very simple statement，yet not so easy to do—Keep your promises. I try to conduct my life in this manner. If you tell someone that you will do something for them，you can’t turn around at the 1ast minute and say, I didn’t do it because it wasn’t convenient. Keeping your promises is also a way to live your life with integrity. That's why it’s important to be aware of your  choice of words, and to live consciously. There were many times that I was not able to keep my promise for example of repaying some money to a friend or colleague, somewhere in the back of my mind I had always intended to repay the debt even if it was years in the future. But that is not a very good way of living. If you consistently live like this you will lose friends because l was not true to my word. It is heartbreaking for both sides.

Especial with Children you need to keep your promise. I get so disturbed when l hear parents trying to sooth a child’s temper and the parent says “I promise一" Later when the child remind the parent or guardian，it becomes clear that the parent had no real thought to keep the promise. The words were just said to placate the child. The parent, as I remember, thought that his or her child would just forget a11 about what was promised. But children have a great memory. Especially when they hear the words I PROMISE. Those words sound stronger than any other words in the English language to a child. We have been taught that those words have power and magic．

[写作内容]

1．以约30个词概括短文的内容要点；

2．以约120个词就“实践你的诺言”这个主题发表你的看法，包含以下的内容要点：

(1)叙述你或你的朋友守信或不守信的一次真实或虚构的经历及其结果。

(2)言而有信让你生机处处；

(3)言而无信使你处处碰壁。

［写作要求］

１、作文中可以使用自己的亲身经历或虚构的故事，也可以参照阅读材料的内容但不得直接引用原文中的句子；     ２、标题自定

[评分标准]   概括准确，语言规范，内容合适，篇章连贯。
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