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 need to come up with a question about the story that requires an understanding of the relationship described in the background paragraph. The generated question should not be answerable without both the background and story. Write a question about the story that requires a relationship in the background paragraph to answer. Check whether your question requires both the background paragraph and the story to answer. If your question can be answered by only one of these, try to rewrite your question so that it requires both. Note that "flipping" a word in the question can give rise to a new question where the answer will be different from the original question. Often, "flipping" a word gives rise to flipping the direction of the relationship, for example, from "increase" to "decrease."

Q: Background Paragraph: The "concentration" of a solid is essentially another way of measuring its density. A certain number of moles are present for a given volume of the solid, and this value does not depend on how much of the solid is present. As the reaction proceeds, the amount of solid reactant will decrease, but so will the volume it occupies. A similar argument can be made for liquids. As a result, the concentrations of solids and liquids are essentially constant over the course of a reaction. 
Story: Cindy has a ball of iron. She measures its density then drops it in a vat of hydrochloric acid. Ashe then removes the irom from the acid noting that the acid ate away as a good potion of the iron. To her suprise however the density of the iron remained constant.

A: Given cindy drops an ice cube in warm water then removes it, will the density of the remaining ice change or remain constant.?
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Q: Background Paragraph: As a star begins to run low on hydrogen, since the initial quantity has been fused into the denser helium gas, the core will contract due to gravity. The collapsing core increases temperature to the point that the star can begin to fuse helium into carbon. When that happens, the outer portion of the star expands greatly due to the higher temperature. The star can expand to 1000 times the diameter of the sun. At this point, the star is called a red giant . If our sun became a red giant, its surface would expand out past the orbit of Mars. Red giants are red because the surface of the star is cooler than white or blue stars, but remain highly visible because of their gigantic size. 
Story: John is an amateur astronomer. He recently found two stars, star A and star B. Upon observation, he figured out that star A is a blue star, but star B is a red giant. He had to do some research to find out the differences between them.

A: Which star would be less visible, star A or star B?
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Q: Background Paragraph: Alpine tundra occurs at high enough altitude at any latitude. Portions of montane grasslands and shrublands ecoregions worldwide include alpine tundra. Large regions of alpine tundra occur in the North American Cordillera, the Alps and Pyrenees of Europe, the Himalaya and Karakoram of Asia, the Andes of South America, and the Eastern Rift mountains of Africa.Alpine tundra occupies high-mountain summits, slopes, and ridges above timberline. Aspect plays a role as well; the treeline often occurs at higher elevations on warmer equator-facing slopes. Because the alpine zone is present only on mountains, much of the landscape is rugged and broken, with rocky, snowcapped peaks, cliffs, and talus slopes, but also contains areas of gently rolling to almost flat topography.Averaging over many locations and local microclimates, the treeline rises 75 metres (245 ft) when moving 1 degree south from 70 to 50°N, and 130 metres (430 ft) per degree from 50 to 30°N. Between 30°N and 20°S, the treeline is roughly constant, between 3,500 and 4,000 metres (11,500 and 13,100 ft). 
Story: Two countries from the same continent have very different climates. Icelandia, located at 70°N latitude, and Uganda, situated just south of 30°N, Icelandia was mostly flat, had a few mountains under 1,000 ft, but Uganda had a mountain range with peaks just under 3,000 ft.

A:
Which country had a higher timberline?
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