托福听力真题原文+题目+答案+mp3下载：significant invention

托福听力真题原文+题目+答案+mp3下载：significant invention

Teacher: Okay, you want to talk about a really significant invention? How about mechanical refrigeration and air conditioning? Think about it, our country would be a very different place without it. For example, how about the fact that hotter regions of the United States like Florida would only have a fraction of the current populations, or that we probably wouldn't have many skyscrapers since you can't open the windows 50 stories up because of high winds. And then open window was about the only way to cool a room in the past. And industrial applications of refrigerated air have been extremely important. (2)Let's look at the printing industry for example. Paper expands and contracts according to the amount of moisture in the air. (So) before air conditioning, it could be impossible to align the inks for printing in color. (So) even something as mundane as color magazines, something we take for granted, it's the regulation of temperature and humidity in the print shop that n.1akes them possible.Now it turns out making something cold is not so easy. I mean to make something hotter, you can heat it with fire for example. But to cool something, sure if it's winter you can get some ice and you're okay, but how practical is that? And what if it isn't winter?Now, one of the guys that who mulled over this problem, was a Doctor John Gorrie. Dr. John Gorrie moved to Apalachicola, Florida in the 1830's. In those days, Florida with its hot, humid summers, its snakes, alligators,mosquitos,and its tropical diseases was a hard place to live.

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听力真题题目如下：

1.What is the lecture mainly about

A、 The origin of an important technological idea

B、The history of the air-conditioning industry

C、Applications and benefits of mechanical refrigeration

D、John Gorrie's trouble with the ice industry

2.What problem did air-conditioning solve in the printing industry

A、Strong winds blowing dirt through open windows

B、Changes in paper size due to humidity

C、Warm temperature slowing the time it took ink to dry

D、Frequent breakdowns of machines that became overheated

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