[Q]: 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. Given the paragraph above, please answer correctly the following question: Will a solids density decrease or stay constant when some of it reacts to a chemical? Hint: 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.
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[A]: constant

[Q]: Milton has just discovered two new planets while looking through his telescope. Luckily, he has invented a device that allows him to analyze far away planets from the comfort of his own home. He boots up the device and discovers that while these two planets are very similar, planet A has much more carbon dioxide in its atmosphere than planet B. While looking through his telescope, he is also able to see that there is the same race of intelligent creatures on both planets. Milton plans to write to his local observatory about his discovery. Given the paragraph above, please answer correctly the following question: Which planet is experiencing less global warming? Hint: Carbon dioxide is the most significant long-lived greenhouse gas in Earth's atmosphere. Since the Industrial Revolution anthropogenic emissions primarily from use of fossil fuels and deforestation have rapidly increased its concentration in the atmosphere, leading to global warming. Carbon dioxide also causes ocean acidification because it dissolves in water to form carbonic acid.
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[A]: planet B

[Q]: Two countries from the same continent have very different climates. Icelandia, located at 70N latitude, and Uganda, situated just south of 30N, 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. Given the paragraph above, please answer correctly the following question: Which country had a lower timberline? Hint: 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 50N, and 130 metres (430 ft) per degree from 50 to 30N. Between 30N and 20S, the treeline is roughly constant, between 3,500 and 4,000 metres (11,500 and 13,100 ft).
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[A]: Icelandia

[Q]: Two pharma students read about antiviral and antibacterial drugs. Manny read about antiviral drugs, while George read about bacteria and antibacterial drugs. Given the paragraph above, please answer correctly the following question: Which student didn't read how people have been able to prevent certain viral diseases by vaccinations for many hundreds of years? Hint: While people have been able to prevent certain viral diseases by vaccinations for many hundreds of years, the development of antiviral drugs to treat viral diseases is a relatively recent development. Antiviral drugs are medications used specifically for treating the symptoms of viral infections. The first antiviral drug was interferon , a substance that is naturally produced by certain immune cells when an infection is detected. Over the past twenty years the development of antiretroviral drugs (also known as antiretroviral therapy, or ART) has increased rapidly. This has been driven by the AIDS epidemic.
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[A]:
George