input: Please answer the following: John is a nuclear scientist who works at the Fermi lab. Today, in front of him he has four samples, sample A, sample B, sample C, and sample D. Sample A is the naturally occurring uranium. Sample B is enriched uranium. Sample C is the U-238, and sample D is the U-235. He needs to figure out how to best use them. Which sample would less likely be used as fuel, sample C or sample D? Hint: Naturally occurring uranium is composed almost entirely of two isotopes, uranium-238 (99%) and uranium-235 (1%). It is the uranium-235 that is fissionable (will undergo fission) and therefore, this is the uranium isotope than can be used for fuel in a nuclear reactor. For uranium to be used as fuel, the percent of uranium-235 must be increased to at least 3%. Uranium in which the U-235 content is more than 1% is called enriched uranium. Somehow, the two isotopes must be separated so that enriched uranium is available for use as fuel. Separating the isotope by chemical means (chemical reactions) is not successful because the isotopes have exactly the same chemistry. The only essential difference between U-238 and U-235 is their atomic masses; as a result, the two isotopes are separated by a physical means that takes advantage of the difference in mass.
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output: sample C

input: Please answer the following: Kathy and Jacob are two coworkers out having a drink at a bar after a day at the office. They both wear glasses and Kathy comments that she hates that she is so farsighted and wishes there was a surgery to fix it. Jacob says that he finds it amusing she is farsighted because he himself is nearsighted. They both laugh at the opposite nature of their eye condition, and then both look at the menu on the other side of the room to decide what drinks to order next. Which person will not have convex lenses in their glasses? Hint: Farsightedness, or hyperopia, is the condition in which distant objects are seen clearly, but nearby objects appear blurry. It occurs when the eyeball is shorter than normal (see Figure below ). This causes images to be focused in a spot that would fall behind the retina (if light could pass through the retina). Hyperopia can be corrected with convex lenses. The lenses focus images farther forward in the eye, so they fall on the retina instead of behind it.
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output: Jacob

input: Please answer the following: Two oceans have divergent plate boundaries at the bottom of their floor. The Arctic ocean has a single dormant divergent plate, while the Pacific ocean has seven diverging tectonic plates under its waters. Which ocean experiences more cooling of hot molten rock? Hint: At the mid-oceanic ridges, two tectonic plates diverge from one another as new oceanic crust is formed by the cooling and solidifying of hot molten rock. Because the crust is very thin at these ridges due to the pull of the tectonic plates, the release of pressure leads to adiabatic expansion (without transfer of heat or matter) and the partial melting of the mantle, causing volcanism and creating new oceanic crust. Most divergent plate boundaries are at the bottom of the oceans; therefore, most volcanic activity on the Earth is submarine, forming new seafloor. Black smokers (also known as deep sea vents) are evidence of this kind of volcanic activity. Where the mid-oceanic ridge is above sea-level, volcanic islands are formed; for example, Iceland.
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output: Pacific

input: Please answer the following: John is very health conscious. He works out regularly, and maintains balanced diet. But his friend Keith doesn't care much about health. He indulges in fast foods, and never exercises. As a result, Keith has type 2 diabetes, but John is free from diabetes. Who would have higher blood pressure, John or Keith? Hint: Type 2 diabetes is much more common than type 1 diabetes. Type 2 diabetes occurs when body cells no longer respond normally to insulin. The pancreas still makes insulin, but the cells of the body can't use it. Being overweight and having high blood pressure increase the chances of developing type 2 diabetes. This type of diabetes usually develops in adulthood. However, it is becoming more common in teens and children because more young people are overweight now than ever before.
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output:
Keith