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: Often, foreign exchange controls can result in the creation of black markets to exchange the weaker currency for stronger currencies. This leads to a situation where the exchange rate for the foreign currency is much higher than the rate set by the government, and therefore creates a shadow currency exchange market. As such, it is unclear whether governments have the ability to enact effective exchange controls.[1]. 
Story: In the beginning of this century there was scandal in the financial market regarding black market trading. A trader named Trader A was working for Bank A. He noticed country M has pegged its currency to a fixed price while country N did not do that. He opted to trade country M currency. Across the aisle his colleague trader B was working for bank B. He traded country N's currency. 
Question: Would trader A be engaged or not be engaged in black market trading?

A: be engaged.
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Q: Background Paragraph: Millions of people in the world jog for exercise. For the most part, jogging can be a healthy way to stay fit. However, problems can also develop for those who jog in the heat. Excessive sweating can lead to electrolyte loss that could be life-threatening. Early symptoms of electrolyte deficiency can include nausea, fatugue, and dizziness. If not treated, individuals can experience muscle weakness and increased heart rate (which could lead to a heart attack). Many sports drinks can be consumed to restore electrolytes quickly in the body. 
Story: Two teams of runners took part in a study about exercise. Red team ran 10 km in the heat, while Green team ran the same distance in the morning in cool weather. The Red team experienced more runners with health problems. 
Question: Which team had fewer runners with muscle weakness?

A: Green.
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Q: Background Paragraph: In many ways, bacterial metabolism provides traits that are useful for ecological stability and for human society. One example is that some bacteria have the ability to fix nitrogen gas using the enzyme nitrogenase. This environmentally important trait can be found in bacteria of most metabolic types listed above. This leads to the ecologically important processes of denitrification, sulfate reduction, and acetogenesis, respectively. Bacterial metabolic processes are also important in biological responses to pollution; for example, sulfate-reducing bacteria are largely responsible for the production of the highly toxic forms of mercury (methyl- and dimethylmercury) in the environment. Non-respiratory anaerobes use fermentation to generate energy and reducing power, secreting metabolic by-products (such as ethanol in brewing) as waste. Facultative anaerobes can switch between fermentation and different terminal electron acceptors depending on the environmental conditions in which they find themselves. 
Story: Two regions, region A and region B, shared a common border, a river. Region A was favorable for sulfate-reducing bacteria and nitrogen fixing bacteria, while region B was more favorable for the developement of Non-respiratory anaerobes and facultative anaerobes. 
Question: Which region had less sulfate reduction?

A:
region B.
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