题目原文：
Large numbers of dinosaur fossils have been discovered in deposits on Alaska’s North Slope, a region that today experiences an extremely cold, arctic climate. One hundred million years ago, when those dinosaurs were alive, the environment of the North Slope was already inhospitable, especially during the winter when it experienced several months of total darkness. How did the dinosaurs survive the wintertime? Paleontologists have proposed that one of the most common North Slope dinosaurs, the elephant-sized edmontosaur (Edmontosaurus), survived the winter by migrating south to more hospitable regions. Several arguments support the migration hypothesis.
First, the edmontosaur’s diet supports the migration hypothesis. Edmontosaurs fed exclusively on plants. Since there would have been no plants growing during the cold and dark North Slope winter, it appears that the edmontosaur must have left for at least part of the year and migrated to more temperate zones to find food.
Second, many edmontosaur skeletons have been unearthed from the same site. This suggests that edmontosaurs lived in herds. Many modern-day migratory animals, such as caribou and buffalo, live and migrate in herds as well. Moving in herds helps animals coordinate their migration. The finding that edmontosaurs lived in herds further supports the migration hypothesis.
Finally, edmontosaurs were physically capable of migrating long distances. To reach more hospitable regions, the edmontosaur had to migrate about 1,600 kilometers southward. To make such a journey, the edmontosaur needed to move at about five kilometers per hour for several weeks, which it certainly could do. These animals could run very fast, reaching speeds up to 45 kilometers per hour. It could have easily used its locomotive power to move to warmer climates during the harsh arctic winters.
题目音频：
学术写作：
大意：
购买商品的时候，怎么做决定？朋友推荐OR网上搜索？
详细原题回忆版：
教授
Let’s continue talking about consumer behavior. We have been discussing different ways people go about choosing what products to buy, and there are many potential sources of information and advice for consumers. In your opinion, which is the better strategy for making purchasing decisions, relying on advice from friends and family, or depending on information from online sources? Why?
Claire
Asking friends and family members for product recommendations might seem like an easier option, but it might take too much time to get all the information you need. An internet search would be much more efficient. There are many consumer magazines available online that compile lots of data to compare the advantages and disadvantages of one product versus another.
Paul
The last time I bought a computer, I just watched a few videos online to make a decision, and now I regret that. My friends could have advised me better because they know my preferences and the kind of features that I am interested in. Consumers should get advice from the people around them to find the most suitable products.
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