[Q]: I read this background article the other day: Arbuscular mycorrhizal fungi vary across many environmental gradients. Their tolerance to freezing and drying is known to shift between AM fungal taxa. AM fungi become less prevalent and diverse at higher soil nutrient and moisture concentrations, presumably because both plants allocate less carbon to AM fungi and AM fungi reallocate their resources to intraradical hyphae in these environmental conditions. Over the long term, these environmental conditions can even create local adaptation between plant hosts, AM fungi and the local soil nutrient concentrations. I am facing a new situation today: Greg and Paul were two neighbors. They were both into mycology. Greg researched AM fungi, while Paul studied other types of mycorrhizal fungi. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which researcher learned more about AM fungi reallocating their resources to intraradical hyphae?
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[A]: Greg

[Q]: I read this background article the other day: A major use for petroleum products is fuel for cars, trucks, airplanes, trains, and other vehicles. The chemical used are usually a mixture of compounds containing several carbon atoms in a chain. When the material is ignited, a massive amount of gas is created almost instantaneously. This increase in volume will move the pistons in an internal combustion engine to provide power. A jet plane works on a similar principle. Air comes into the front of the engine and mixes with the jet fuel. This mixture is ignited and the gases formed create a lot of pressure to push the plane forward. The idea can be seen even more clearly in the case of a rocket launch. The ignition of the fuel (either solid-state or liquid) creates gases produced under great pressure that pushes the rocket up. I am facing a new situation today: Two sister countries used petroleum in different ways. Norway used it to make plastics, while Sweden used it for fuel. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which country used more fuel for airplanes?
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[A]: Sweden

[Q]: I read this background article the other day: All of these animal behaviors are important. They help the animals get food for energy, make sure their young survive, or ensure that they, themselves, survive. Behaviors that help animals or their young survive, increase the animals' fitness. Animals with higher fitness have a better chance of passing their genes on to the next generation. If genes control behaviors that increase fitness, the behaviors become more common in the species. This occurs through the process of evolution by natural selection. I am facing a new situation today: Two bears are living in the same forest. One bear, named Teddy, often runs and is active in its daily life. The other bear, Fluffy, is lazy and hardly moves at all. Their levels of fitness are very different with Teddy having a much higher overall fitness level than Fluffy. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Who will make a worse parent?
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[A]: Fluffy

[Q]: I read this background article the other day: At the end of the Proterozoic, the supercontinent Pannotia had broken apart into the smaller continents Laurentia, Baltica, Siberia and Gondwana. During periods when continents move apart, more oceanic crust is formed by volcanic activity. Because young volcanic crust is relatively hotter and less dense than old oceanic crust, the ocean floors rise during such periods. This causes the sea level to rise. Therefore, in the first half of the Paleozoic, large areas of the continents were below sea level.Early Paleozoic climates were warmer than today, but the end of the Ordovician saw a short ice age during which glaciers covered the south pole, where the huge continent Gondwana was situated. Traces of glaciation from this period are only found on former Gondwana. During the Late Ordovician ice age, a few mass extinctions took place, in which many brachiopods, trilobites, Bryozoa and corals disappeared. These marine species could probably not contend with the decreasing temperature of the sea water.The continents Laurentia and Baltica collided between 450 and 400 Ma, during the Caledonian Orogeny, to form Laurussia (also known as Euramerica). Traces of the mountain belt this collision caused can be found in Scandinavia, Scotland, and the northern Appalachians. In the Devonian period (416359 Ma) Gondwana and Siberia began to move towards Laurussia. The collision of Siberia with Laurussia caused the Uralian Orogeny, the collision of Gondwana with Laurussia is called the Variscan or Hercynian Orogeny in Europe or the Alleghenian Orogeny in North America. The latter phase took place during the Carboniferous period (359299 Ma) and resulted in the formation of the last supercontinent, Pangaea.By 180 Ma, Pangaea broke up into Laurasia and Gondwana. I am facing a new situation today: Two space explorers are flying around through an unknown galaxy when they discover two new planets. Given that these planets have no names, the explorers decide to name them after themselves. The planet of Sarahn is currently going through a large geographic shift. Many of the continents on the planet are currently breaking apart and moving. Timon, however, has been a stable planet with no continental moving for quite awhile now. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Is the volcanic crust on Sarahn or Timon cooler?
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[A]:
Timon