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.

Q: Background Paragraph: An apex predator, also known as an alpha predator or top predator, is a predator at the top of a food chain, with no natural predators.Apex predators are usually defined in terms of trophic dynamics, meaning that they occupy the highest trophic levels. Food chains are often far shorter on land, usually limited to being secondary consumers for example, wolves prey mostly upon large herbivores (primary consumers), which eat plants (primary producers). The apex predator concept is applied in wildlife management, conservation and ecotourism.
Story: Two cousins were fascinated about food chains in nature. Liam started reading about apex predators, while Fox read about grazers and large herbivores.
Question: Which cousin learned less about primary consumers?

A: Liam.
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Q: Background Paragraph: A major use for petroleum products is fuel for cars, trucks, airplanes, trains, and other vehicles. The chemical used are usually a mixture of compounds containing several carbon atoms in a chain. When the material is ignited, a massive amount of gas is created almost instantaneously. This increase in volume will move the pistons in an internal combustion engine to provide power. A jet plane works on a similar principle. Air comes into the front of the engine and mixes with the jet fuel. This mixture is ignited and the gases formed create a lot of pressure to push the plane forward. The idea can be seen even more clearly in the case of a rocket launch. The ignition of the fuel (either solid-state or liquid) creates gases produced under great pressure that pushes the rocket up.
Story: Big town and Fair town both used petroleum products. Big town used them to make plastics and related materials, but didn't use it for gas, because they were environmentally conscious and used only electric vehicles for transportation. Fair town used petroleum for fuel mostly.
Question: Which town used petroleum to make fuel for cars?

A: Fair.
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Q: Background Paragraph: Fish mortality is a parameter used in fisheries population dynamics to account for the loss of fish in a fish stock through death. The mortality can be divided into two types:

Natural mortality: the removal of fish from the stock due to causes not associated with fishing. Such causes can include disease, competition, cannibalism, old age, predation, pollution or any other natural factor that causes the death of fish. In fisheries models natural mortality is denoted by (M).[1]
Fishing mortality: the removal of fish from the stock due to fishing activities using any fishing gear.[1] It is denoted by (F) in fisheries models.
Story: Tony is about to go on two fishing trips in the up coming week. On Friday, he is going to Bear Lake, which is located near a factory that has been known to dump waste into the lake. On Saturday, he is going to Fox Lake, which is in a secluded valley.
Question: Which day will Tony visit a lake that more likely has more fish?

A:
Saturday.
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