instruction:
 You are given a background paragraph that describes one or more causal or physical relationships, such as a relationship in economics, scientific law, or nature. You need to come up with a fictional story that makes use of the concepts or the relationship described in the provided paragraph. Make sure that your story does not repeat the relation in the given paragraph (e.g., by avoiding verbatim copies of the given paragraph). Start by reading the background paragraph, and determine what relationship(s) are in the paragraph. Write a story that involves the relationship(s) that you determined are in the background paragraph. Try to use your own words as much as possible and not repeat the background paragraph. Feel free to make up places and events as long as they tie back to the background paragraph in a way that you can ask a question about.
question:
Background Paragraph: Another thing we can see in this animation is that particles are constantly colliding with one another. One assumption that we make when talking about collisions between gas particles is that they are completely elastic collisions. In an elastic collision , momentum is conserved, which means that none of the kinetic energy of the colliding particles is lost in some other form (such as the emission of light). This makes sense, because if energy were lost in collisions, the speeds of the particles would gradually decrease over time, and eventually everything would condense down into a solid form.
answer:
Dan is in his physics lab. He is experimenting with colliding particles. He has two samples of particles, sample A and sample B. Sample A contains gas particles, but sample B does not contain gas particles.


question:
Background Paragraph: Some materials have negative heats of solution; the dissolution of one of these solutes in water is an exothermic process. Heat is released, causing a net increase in the temperature of the solution. Conversely, other substances have positive heats of solution. For example, the dissolution of potassium nitrate in water is an endothermic process. The resulting absorption of energy causes the solution to become colder. Calculations involving heats of solutions follow the same basic approach that we have used with other enthalpy problems.
answer:
A scientist is in the lab testing mixing water with different chemicals. While working with chemical A he notes that the water becomes colder after combining them. With chemical B the water becomes much warmer.


question:
Background Paragraph: The epidermis also contains melanocytes, which are cells that produce melanin. Melanin is the brownish pigment that gives skin much of its color. Everyone has about the same number of melanocytes, but the melanocytes of people with darker skin produce more melanin. The amount of melanin produced is determined by heredity and exposure to UV light, which increases melanin output. Exposure to UV light also stimulates the skin to produce vitamin D. Because melanin blocks UV light from penetrating the skin, people with darker skin may be at greater risk of vitamin D deficiency.
answer:

Jacob has lived in a city in Sweden for most of his life. His favorite hobbies are reading and playing videogames so he rarely goes outside. Even as a kid, he almost never played outside and instead was in his house most of the time. Martin lives in the middle of the Sahara desert in a small town. The sun almost never stops beating down on Martin during the day and it's hard to find shade where he lives.