1．为什么管嘴出流时，阻力增加了，泄流量反而增大？

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国家开放大学 / 流体力学

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1、存款账户按管理要求不同划分为 a.专用存款b.一般存款账户c.基本存款账户d.临时存款账户金融企业会计

Passage 1 The United States covers a large part of the North American continent. Its neighbors are Canada to the north and Mexico to the south. Although the United States is a big country, it is not the largest in the world. In 2000, its population was over 222 million. When this land first became a nation, after winning its independence from England, it had thirteen states. Each of the states was represented on the American flag by a star. All these states were in the eastern part of the continent. As the nation grew toward the west, new states were added and new stars appeared on the flag. For a long time, there were 48 stars. In 1959, however, two more stars were added to the flag, representing the new states of Alaska and Hawaii. Passage 1 The United States covers a large part of the North American continent. Its neighbors are Canada to the north and Mexico to the south. Although the United States is a big country, it is not the largest in the world. In 2000, its population was over 222 million. When this land first became a nation, after winning its independence from England, it had thirteen states. Each of the states was represented on the American flag by a star. All these states were in the eastern part of the continent. As the nation grew toward the west, new states were added and new stars appeared on the flag. For a long time, there were 48 stars. In 1959, however, two more stars were added to the flag, representing the new states of Alaska and Hawaii. Indians were the first people of the land which is now the United States. There are still many thousands of Indians now living in all parts of the country. Sometimes it is said that the Indians are“the only real Americans”. Most Americans come from all over the world. Those who came first in greatest numbers to make their homes on the eastern coast of North America were mostly from England.It is for that reason that the language of the United States is English and that its culture and customs are more like those of England than those of any other country in the world.This story teaches us two lessons: 1. There is power of life and death in the tongue. An encouraging word to someone who is down can lift him up and help him make it through the day. 2. A destructive word to someone who is down can be what it takes to kill him. Be careful of what you say. The power of words is sometimes hard to understand because an encouraging word can go such a long way. Anyone can speak words that tend to rob another of the spirit to continue in difficult times. Special is the individual who will take the time to encourage another. 6. Which of the following is TRUE? A.America is the largest country in the world. B.The United States lies next toCanada and Mexico. C.America covers most part of the North American continent. D.Mexico is to the north of Canada. 7. After winning its independence, the United States _ _ _ _ _ _ _ _ _ . A. had nothing to do with England B.made India part of its land C.mainly developed westward D.took over parts of Canada and Mexico 8. The United States didn’t have _ _ _ _ _ _ states until _ _ _ _ _ _ _ _ . A.thirteen; 1959 B.fifty; 1959 C.fifty; this land first became a nation D.fifty;1964 9. Why is English the language of America? A.Because English is the native language of the Indians. B.Because most Americans come from all over the world. C.Because Canada is America’s nearest neighbor. D. Because most of thepeople who first settled in America were fromEngland. 10. The best title for the passage is“ _ _ _ _ _ _ _ _ _ ”. A.the States of America B.The language of America C.The United States of America D.The Culture and Customs of America统考英语阅读理解

29、以下关于多媒体技术的描述中，正确的是______。 A.多媒体技术只能用来观看的DVD盘 B.多媒体技术只能用来观看的VCD盘 C.多媒体技术中的“媒体”概念特指新闻传播媒体 D.多媒体技术是指将多种媒体进行有机组合而成的一种新的媒体应用系统计算机统考

【单项选择题】管理方格理论的研究者认为，( )风格的管理者工作最佳。 a.任务型管理b.团队型管理c.中庸型管理d.乡村俱乐部型管理现代企业管理方法

11、下列情况中，破坏了信息保密性的攻击是_______。 A.假冒他人地址发送信息 B.信息发送方否认自己的发信行为 C.信息加密被破译 D.信息在传输中途被篡改计算机统考

89、______是第四代计算机的典型代表。 A.巨型机 B.微型机 C.小型机 D.大中型机计算机统考