【正确答案】According to the lecture, railroads had two main impacts on American business. First of all, the railways made shipping goods almost anywhere easy and fast. This in turn encouraged the growth of factories and retailers. A city-wide business now became nationwide or even covered the continent.
Second, factories were no longer closely tied to energy-rich areas like coal fields, or iron-mining areas. Factories could be built wherever businessmen chose. This tended to be in areas offering cheap and plentiful labor.

【答案解析】[听力原文]
W: Living in this, the late Automobile Age, it is difficult to imagine the impacts that railroads had on American business and culture. In today's lecture, I'd like to sketch out two broad effects railroads had on business.
First of all and most obviously, railroads made for the easy shipment of goods. A journey that took all day by horse cart, now took an hour and soon less. A week's travel shrank to less than half a day. So, say you were a watchmaker. Before the railroad, you could only sell to customers in your city. With the coming of trains, you could sell anywhere the railroad went. That's not all. You could now sell everywhere on a global scale. That is, your number of potential customers multiplied hugely! So that's right, the easy shipment of goods was an invitation for making shops and factories bigger and bigger. Second, factories could now be located anywhere. In the early days of industry factories were tied to coal-mining regions because their machinery ran on steam power, and steam takes heat; the fires need coal. The early industrial regions, the north of England, Germany's Ruhr region, and the Midwest were all coal-rich areas. They were also iron- producing regions as well. With trains, though, coal and ore could be transported to the population centers. This not only made for widespread industry, it also drove down the price of labor. Factories could now be relocated to wherever workers were cheap...just like today!

Alternative Wording(替换表达)
Synonyms (a)impact—effect (b)goods—merchandise
(c)encourage—lead to (d)businessman—entrepreneur
Paraphrases 1. As a result, factories grew and retailers expanded.
2. Second, factories were no longer bound to their sources of raw materials or energy supplies.