You are given a background paragraph that describes one or more causal or qualitative relationships such as a relationship in economics or a scientific law and a story that makes use of the concepts or the relationship described in the provided paragraph. You need to come up with a question about the story that requires an understanding of the relationship described in the background paragraph. The generated question should not be answerable without both the background and story. Write a question about the story that requires a relationship in the background paragraph to answer. Check whether your question requires both the background paragraph and the story to answer. If your question can be answered by only one of these, try to rewrite your question so that it requires both. Note that "flipping" a word in the question can give rise to a new question where the answer will be different from the original question. Often, "flipping" a word gives rise to flipping the direction of the relationship, for example, from "increase" to "decrease."

Q: Background Paragraph: Another possible benefit of aggregation is to protect against predation by group anti-predator behavior. Many species exhibit higher rates of predator vigilance behavior per individual at lower density. This increased vigilance might result in less time and energy spent on foraging, thus reducing the fitness of an individual living in smaller groups. One striking example of such shared vigilance is exhibited by meerkats. Meanwhile, other species move in synchrony to confuse and avoid predators such as schools of sardines and flocks of starlings. The confusion effect that this herding behavior would have on predators will be more effective when more individuals are present.Cooperative feeding.
Story: In the sub-Saharan African country of Nigeria, there are two main species that tend to travel in groups. The antelope tend to travel in groups in high numbers, and thus exhibit a high density. Meanwhile, the bison tend to travel in groups of small numbers, and therefore exhibit low density. Both the antelope and the bison have natural predators that exist in Nigeria.

A: Individuals from which species, the antelope or the bison, will have higher rates of predator vigilance behavior?
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Q: Background Paragraph: The lungs of mammals are unique in having alveoli . These are tiny, sac-like structures. Each alveolus is surrounded by a network of very small blood vessels (see Figure below ). Because there are millions of alveoli in each lung, they greatly increase the surface area for gas exchange between the lungs and bloodstream. Human lungs, for example, contain about 300 million alveoli. They give the lungs a total surface area for gas exchange of up to 90 square meters (968 square feet). That's about as much surface area as one side of a volleyball court!.
Story: Two students learned about respiratory systems in animals. Dana learned more about mammalian lungs, while Barry learned more about the lungs of birds.

A: Which student learned less about a network of very small blood vessels?
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Q: Background Paragraph: When the temperature of reactants is higher, the rate of the reaction is faster. At higher temperatures, particles of reactants have more energy, so they move faster. They are more likely to bump into one another and to collide with greater force. For example, when you fry an egg, turning up the heat causes the egg to cook faster. The same principle explains why storing food in a cold refrigerator reduces the rate at which food spoils (see Figure below ). Both food frying and food spoiling are chemical reactions that happen faster at higher temperatures.
Story: Ned learned about reactions at a higher temperature for his physics class, while Paul had to learn about reactions at lower temperatures.

A:
Which person didn't study about how storing food in a cold refrigerator reduced the rate at which food spoiled?
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