Problem: Zhejiang:

Han Chinese make up the vast majority of the population, and the largest Han subgroup are the speakers of Wu varieties of Chinese. There are also 400,000 members of ethnic minorities, including approximately 200,000 She people and approximately 20,000 Hui Chinese[citation needed]. Jingning She Autonomous County in Lishui is the only She autonomous county in China.

Where is the only She autonomous county in Japan?
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A: unanswerable

Problem: During the 1930s solid fuel rockets were under development in the Soviet Union and Britain. In Britain the interest was for anti-aircraft fire, it quickly became clear that guidance would be required for precision. However, rockets, or 'unrotated projectiles' as they were called could the used for anti-aircraft barrages. A 2-inch rocket using HE or wire obstacle warheads was introduced first to deal with low-level or dive bombing attacks on smaller targets such as airfields. The 3-inch was in development at the end of the inter-war period.
How big was the rocket that was introduced to handle dive bombing attacks?
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Answer: 2-inch

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Brass, which is an alloy of copper and zinc, has been used since at least the 10th century BC in Judea and by the 7th century BC in Ancient Greece. Zinc metal was not produced on a large scale until the 12th century in India and was unknown to Europe until the end of the 16th century. The mines of Rajasthan have given definite evidence of zinc production going back to the 6th century BC. To date, the oldest evidence of pure zinc comes from Zawar, in Rajasthan, as early as the 9th century AD when a distillation process was employed to make pure zinc. Alchemists burned zinc in air to form what they called "philosopher's wool" or "white snow".
What early process was used to dissolve zinc?
A: unanswerable

Context and question: The electrolysis of water is a simple method of producing hydrogen. A low voltage current is run through the water, and gaseous oxygen forms at the anode while gaseous hydrogen forms at the cathode. Typically the cathode is made from platinum or another inert metal when producing hydrogen for storage. If, however, the gas is to be burnt on site, oxygen is desirable to assist the combustion, and so both electrodes would be made from inert metals. (Iron, for instance, would oxidize, and thus decrease the amount of oxygen given off.) The theoretical maximum efficiency (electricity used vs. energetic value of hydrogen produced) is in the range 8094%.
Where does the gaseous hydrogen form at?
Answer: cathode

Question: Perhaps the most famous raid by Oeselian pirates occurred in 1187, with the attack on the Swedish town of Sigtuna by Finnic raiders from Couronia and Oesel. Among the casualties of this raid was the Swedish archbishop Johannes. The city remained occupied for some time, contributing to its decline as a center of commerce in the 13th century and the rise of Uppsala, Visby, Kalmar and Stockholm. The Livonian Chronicle describes the Oeselians as using two kinds of ships, the piratica and the liburna. The former was a warship, the latter mainly a merchant ship. A piratica could carry approximately 30 men and had a high prow shaped like a dragon or a snakehead and a rectangular sail. Viking-age treasures from Estonia mostly contain silver coins and bars. Saaremaa has the richest finds of Viking treasures after Gotland in Sweden. This strongly suggests that Estonia was an important transit country during the Viking era.
Is there an answer to this question: What year did the Oeselian pirates carry out a famous raid?

Answer: 1187

Problem: Sino-Tibetan relations during the Ming dynasty:

In 1358, the Sakya viceregal regime installed by the Mongols in Tibet was overthrown in a rebellion by the Phagmodru myriarch Tai Situ Changchub Gyaltsen (13021364). The Mongol Yuan court was forced to accept him as the new viceroy, and Changchub Gyaltsen and his successors, the Phagmodrupa Dynasty, gained de facto rule over Tibet.

Which dynasty became ruler of Tibet?
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A:
the Phagmodrupa Dynasty