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: Although some lipids in the diet are essential, excess dietary lipids can be harmful. Because lipids are very high in energy, eating too many may lead to unhealthy weight gain. A high-fat diet may also increase lipid levels in the blood. This, in turn, can increase the risk for health problems such as cardiovascular disease. The dietary lipids of most concern are saturated fatty acids, trans fats, and cholesterol. For example, cholesterol is the lipid mainly responsible for narrowing arteries and causing the disease atherosclerosis.
Story: Two groups of people were part of a science study. Group A ate lots of fats(lipids), while Group B had a more balanced diet with few fats. Group A gained a lot of weight over the course of the 6 month study.
Question: Which group had increased lipid levels in the blood?

A: Group A.
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Q: Background Paragraph: Alcoholic beverages do not make the entire body warmer.[361] The reason that alcoholic drinks create the sensation of warmth is that they cause blood vessels to dilate and stimulate nerve endings near the surface of the skin with an influx of warm blood. This can actually result in making the core body temperature lower, as it allows for easier heat exchange with a cold external environment.
Story: A scientist studied the effects of alcoholic beverages on the human body during severe weather exposure. He decided to experiment on himself. He stood in -30 degrees weather for 2 hours and called it experiment A. He then repeated the experiment, the only difference being that he consumed a pint of hard liquor before and during those two hours, and that was called experiment B.
Question: When did the scientist's blood vessels dilate less, during experiment A, or during B?

A: experiment A.
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Q: Background Paragraph: When a solid substance is involved in a chemical reaction, only the matter at the surface of the solid is exposed to other reactants. If a solid has more surface area, more of it is exposed and able to react. Therefore, increasing the surface area of solid reactants increases the reaction rate. Look at the hammer and nails pictured in the Figure below . Both are made of iron and will rust when the iron combines with oxygen in the air. However, the nails have a greater surface area, so they will rust faster.
Story: Andy is participating in this years science fair. He is testing how fast metal takes to rust. He rakes 3 pieces of iron one is a cube, and the other is a sheet both weighing the same. It takes the cube almost a week to fully rust but the sheet only takes 2 days. The only difference between the two is that the sheet has more surface area. He tries this again with a cylinder so the surface area is larger than the cube but smaller than the sheet and it takes about 4 days to fully rust.
Question: Will making the surface area of iron larger increase or decrease how fast it rusts?

A:
increase.
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