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 are also given a question about the story that requires an understanding of the relationship described in the background paragraph and the story. You need to come up with an answer to the given question; the answer will be a span from either the question or the story. In order to correctly answer the given question, you need to understand the relationship mentioned in the background paragraph and should be able to use it to understand that in the story. Your answer can not consist of any word that is not mentioned in any of these: the background paragraph, the story, or the question. You can directly copy and paste a span from the story or the question while answering the given question.
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Question: Background Paragraph: Predators play an important role in an ecosystem. For example, if they did not exist, then a single species could become dominant over others. Grazers on a grassland keep grass from growing out of control. Predators can be keystone species . These are species that can have a large effect on the balance of organisms in an ecosystem. For example, if all of the wolves are removed from a population, then the population of deer or rabbits may increase. If there are too many deer, then they may decrease the amount of plants or grasses in the ecosystem. Decreased levels of producers may then have a detrimental effect on the whole ecosystem. In this example, the wolves would be a keystone species. 
Story: Two students studied animal behavior for the biology class. Ned studied more about predators, while Kim studied more about herbivores. 
Question: Which student learned less about deer?

Answer: Ned.


Question: Background Paragraph: An equilibrium can also be disrupted by the full or partial removal of a reactant or product. If the concentration of a substance is decreased, the system will respond by favoring the reaction that replaces that substance. In the industrial Haber-Bosch process, NH 3 is removed from the equilibrium system as the reaction proceeds. As a result, the forward reaction is favored so that more NH 3 will be produced. The concentrations of N 2 and H 2 decrease. Continued removal of NH 3 will eventually force the reaction to go to completion until all of the reactants are used up. If either N 2 or H 2 were removed from the equilibrium system, the reverse reaction would be favored, and the concentration of NH 3 would decrease. 
Story: Jennifer and Justin are examining the principle of chemical equilibrium in their second year organic chemistry course. They are performing a reaction that involves hydrogen gas and glucose as the starting reactants, and the products formed in the reaction are carbon dioxide and oxygen gas. Jennifer and Justin add the materials, and then wait until the reaction has reached equilibrium. Afterwards, Jennifer removes glucose from her reaction mixture, while Justin removes carbon dioxide from his reaction mixture. 
Question: Which person's reaction, Jennifer's or Justin's, will begin producing more glucose?

Answer: Jennifer's.


Question: Background Paragraph: Ecology is the study of ecosystems. An ecosystem consists of all the living and nonliving components of the habitat. Whereas nutrients and certain elements are recycled through ecosystems, energy moves in just one direction. Many interactions among species within an ecosystem are centered around the flow of energy. The formation of ecosystems, from new land to current habitats, is usually based on the pioneer species, and these species are able to live in an area due to the nonliving factors, such as the climate, the soil and the amount of rainfall, of that area. The populations within an ecosystem also determine the stability of the system. Recent tremendous increases in the human population have raised many important ecological issues. 
Story: Two brothers liked natural sciences. Ben decided to study Ecology, while his brother Dan decided to study Geography. They studied a lot and became very good at these subjects. 
Question: Which brother studied fewer nonliving components of the habitat?

Answer:
Dan.