Problem: Given the question: Extract the answer to the question from the following context. Question: What were women trained to do if need be? Context: Maintaining the household was the main duty of samurai women. This was especially crucial during early feudal Japan, when warrior husbands were often traveling abroad or engaged in clan battles. The wife, or okugatasama (meaning: one who remains in the home), was left to manage all household affairs, care for the children, and perhaps even defend the home forcibly. For this reason, many women of the samurai class were trained in wielding a polearm called a naginata or a special knife called the kaiken in an art called tantojutsu (lit. the skill of the knife), which they could use to protect their household, family, and honor if the need arose.
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The answer is:
defend the home forcibly


Problem: Given the question: Extract the answer to the question from the following context. Question: What country pushed the boundaries for railway power delivery? 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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The answer is:
Soviet Union


Problem: Given the question: Extract the answer to the question from the following context. Question: What is amplified by playback equipment? Context: Due to recording mastering and manufacturing limitations, both high and low frequencies were removed from the first recorded signals by various formulae. With low frequencies, the stylus must swing a long way from side to side, requiring the groove to be wide, taking up more space and limiting the playing time of the record. At high frequencies, hiss, pops, and ticks are significant. These problems can be reduced by using equalization to an agreed standard. During recording the amplitude of low frequencies is reduced, thus reducing the groove width required, and the amplitude at high frequencies is increased. The playback equipment boosts bass and cuts treble so as to restore the tonal balance in the original signal; this also reduces the high frequency noise. Thus more music will fit on the record, and noise is reduced.
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The answer is:
bass