In this task, you are given a question and a context passage. You have to answer the question based on the given passage.
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Question: who avenged Chu'Tsai's forefathers?, Context: Genghis Khan realised that he needed people who could govern cities and states conquered by him. He also realised that such administrators could not be found among his Mongol people because they were nomads and thus had no experience governing cities. For this purpose Genghis Khan invited a Khitan prince, Chu'Tsai, who worked for the Jin and had been captured by the Mongol army after the Jin dynasty was defeated. Jin had captured power by displacing Khitan. Genghis told Chu'Tsai, who was a lineal descendant of Khitan rulers, that he had avenged Chu'Tsai's forefathers. Chu'Tsai responded that his father served the Jin dynasty honestly and so did he; also he did not consider his own father his enemy, so the question of revenge did not apply. This reply impressed Genghis Khan. Chu'Tsai administered parts of the Mongol Empire and became a confidant of the successive Mongol Khans.

Answer: Genghis Khan


Question: What do you need in addition to the LaserDisc in order to experience surround sound?, Context: Only one 5.1 surround sound option exists on a given LaserDisc (either Dolby Digital or DTS), so if surround sound is desired, the disc must be matched to the capabilities of the playback equipment (LD Player and Receiver/Decoder) by the purchaser. A fully capable LaserDisc playback system includes a newer LaserDisc player that is capable of playing digital tracks, has a digital optical output for digital PCM and DTS audio, is aware of AC-3 audio tracks, and has an AC-3 coaxial output; an external or internal AC-3 RF demodulator and AC-3 decoder; and a DTS decoder. Many 1990s A/V receivers combine the AC-3 decoder and DTS decoder logic, but an integrated AC-3 demodulator is rare both in LaserDisc players and in later A/V receivers.

Answer: playback equipment


Question: What was Western Thrace and Greek Macedonia considered in regards to the Ottoman empire?, Context: Following the Fall of Constantinople on 29 May 1453, many Greeks sought better employment and education opportunities by leaving for the West, particularly Italy, Central Europe, Germany and Russia. Greeks are greatly credited for the European cultural revolution, later called, the Renaissance. In Greek-inhabited territory itself, Greeks came to play a leading role in the Ottoman Empire, due in part to the fact that the central hub of the empire, politically, culturally, and socially, was based on Western Thrace and Greek Macedonia, both in Northern Greece, and of course was centred on the mainly Greek-populated, former Byzantine capital, Constantinople. As a direct consequence of this situation, Greek-speakers came to play a hugely important role in the Ottoman trading and diplomatic establishment, as well as in the church. Added to this, in the first half of the Ottoman period men of Greek origin made up a significant proportion of the Ottoman army, navy, and state bureaucracy, having been levied as adolescents (along with especially Albanians and Serbs) into Ottoman service through the devshirme. Many Ottomans of Greek (or Albanian or Serb) origin were therefore to be found within the Ottoman forces which governed the provinces, from Ottoman Egypt, to Ottomans occupied Yemen and Algeria, frequently as provincial governors.

Answer:
the central hub


