[Q]: Extract the answer to the question from the following context. Question: DC produces fewer problems with what kinds of support infrastructure used with trains? Context: There has, however, been interest among railroad operators in returning to DC use at higher voltages than previously used. At the same voltage, DC often has less loss than AC, and for this reason high-voltage direct current is already used on some bulk power transmission lines. DC avoids the electromagnetic radiation inherent with AC, and on a railway this also reduces interference with signalling and communications and mitigates hypothetical EMF risks. DC also avoids the power factor problems of AC. Of particular interest to railroading is that DC can supply constant power with a single ungrounded wire. Constant power with AC requires three-phase transmission with at least two ungrounded wires. Another important consideration is that mains-frequency 3-phase AC must be carefully planned to avoid unbalanced phase loads. Parts of the system are supplied from different phases on the assumption that the total loads of the 3 phases will even out. At the phase break points between regions supplied from different phases, long insulated supply breaks are required to avoid them being shorted by rolling stock using more than one pantograph at a time. A few railroads have tried 3-phase but its substantial complexity has made single-phase standard practice despite the interruption in power flow that occurs twice every cycle. An experimental 6 kV DC railway was built in the Soviet Union.
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[A]: signalling and communications
input: Please answer the following: Extract the answer to the question from the following context. Question: For provinces that couldn't pay taxes what did they not get in return? Context: In fact, there was an eighth province, the County of Drenthe, but this area was so poor it was exempt from paying federal taxes and as a consequence was denied representation in the States General. Each province was governed by the Provincial States, the main executive official (though not the official head of state) was a raadspensionaris. In times of war, the stadtholder, who commanded the army, would have more power than the raadspensionaris.
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output: representation
Please answer this: Extract the answer to the question from the following context. Question: Which of the following is not a body of water: the Taiwan Strait or the Politburo? Context: On 27 June 1950, two days after the KPA invaded and three months before the Chinese entered the war, President Truman dispatched the United States Seventh Fleet to the Taiwan Strait, to prevent hostilities between the Nationalist Republic of China (Taiwan) and the People's Republic of China (PRC). On 4 August 1950, with the PRC invasion of Taiwan aborted, Mao Zedong reported to the Politburo that he would intervene in Korea when the People's Liberation Army's (PLA) Taiwan invasion force was reorganized into the PLA North East Frontier Force. China justified its entry into the war as a response to "American aggression in the guise of the UN".
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Answer: the Politburo
Problem: Extract the answer to the question from the following context. Question: What is a student given as feedback on schoolwork? Context: In higher organisms (like people), these two modes of perception combine into what Whitehead terms "symbolic reference", which links appearance with causation in a process that is so automatic that both people and animals have difficulty refraining from it. By way of illustration, Whitehead uses the example of a person's encounter with a chair. An ordinary person looks up, sees a colored shape, and immediately infers that it is a chair. However, an artist, Whitehead supposes, "might not have jumped to the notion of a chair", but instead "might have stopped at the mere contemplation of a beautiful color and a beautiful shape." This is not the normal human reaction; most people place objects in categories by habit and instinct, without even thinking about it. Moreover, animals do the same thing. Using the same example, Whitehead points out that a dog "would have acted immediately on the hypothesis of a chair and would have jumped onto it by way of using it as such." In this way symbolic reference is a fusion of pure sense perceptions on the one hand and causal relations on the other, and that it is in fact the causal relationships that dominate the more basic mentality (as the dog illustrates), while it is the sense perceptions which indicate a higher grade mentality (as the artist illustrates).

A: grade
Problem: Given the question: Extract the answer to the question from the following context. Question: What company makes the Xbox? Context: The Xbox 360 sold much better than its predecessor, and although not the best-selling console of the seventh-generation, it is regarded as a success since it strengthened Microsoft as a major force in the console market at the expense of well-established rivals. The inexpensive Nintendo Wii did sell the most console units but eventually saw a collapse of third-party software support in its later years, and it has been viewed by some as a fad since the succeeding Wii U had a poor debut in 2012. The PlayStation 3 struggled for a time due to being too expensive and initially lacking quality titles, making it far less dominant than its predecessor, the PlayStation 2, and it took until late in the PlayStation 3's lifespan for its sales and game titles to reach parity with the Xbox 360. TechRadar proclaimed that "Xbox 360 passes the baton as the king of the hill a position that puts all the more pressure on its successor, Xbox One".
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The answer is:
Microsoft
Problem: Extract the answer to the question from the following context. Question: What did Frederick offer for Saxony? Context: The Treaty of Hubertusburg, between Austria, Prussia, and Saxony, was signed on February 15, 1763, at a hunting lodge between Dresden and Leipzig. Negotiations had started there on December 31, 1762. Frederick, who had considered ceding East Prussia to Russia if Peter III helped him secure Saxony, finally insisted on excluding Russia (in fact, no longer a belligerent) from the negotiations. At the same time, he refused to evacuate Saxony until its elector had renounced any claim to reparation. The Austrians wanted at least to retain Glatz, which they had in fact reconquered, but Frederick would not allow it. The treaty simply restored the status quo of 1748, with Silesia and Glatz reverting to Frederick and Saxony to its own elector. The only concession that Prussia made to Austria was to consent to the election of Archduke Joseph as Holy Roman emperor.

A:
East Prussia