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 ruled Bithynia before Bas?, Context: The Bithynians were a Thracian people living in northwest Anatolia. After Alexander's conquests the region of Bithynia came under the rule of the native king Bas, who defeated Calas, a general of Alexander the Great, and maintained the independence of Bithynia. His son, Zipoetes I of Bithynia maintained this autonomy against Lysimachus and Seleucus I, and assumed the title of king (basileus) in 297 BCE. His son and successor, Nicomedes I, founded Nicomedia, which soon rose to great prosperity, and during his long reign (c. 278 – c. 255 BCE), as well as those of his successors, the kingdom of Bithynia held a considerable place among the minor monarchies of Anatolia. Nicomedes also invited the Celtic Galatians into Anatolia as mercenaries, and they later turned on his son Prusias I, who defeated them in battle. Their last king, Nicomedes IV, was unable to maintain himself against Mithridates VI of Pontus, and, after being restored to his throne by the Roman Senate, he bequeathed his kingdom by will to the Roman republic (74 BCE).

Answer: Calas


Question: How much can fixing water contamination improve child mortality rates overall?, Context: Given that water contamination is a major means of transmitting diarrheal disease, efforts to provide clean water supply and improved sanitation have the potential to dramatically cut the rate of disease incidence. In fact, it has been proposed that we might expect an 88% reduction in child mortality resulting from diarrheal disease as a result of improved water sanitation and hygiene. Similarly, a meta-analysis of numerous studies on improving water supply and sanitation shows a 22–27% reduction in disease incidence, and a 21–30% reduction in mortality rate associated with diarrheal disease.

Answer: 88%


Question: Which occurred later: the repeat performance of the Beethoven Seventh Symphony or Chopin's signs of serious illness?, Context: From 1842 onwards, Chopin showed signs of serious illness. After a solo recital in Paris on 21 February 1842, he wrote to Grzymała: "I have to lie in bed all day long, my mouth and tonsils are aching so much." He was forced by illness to decline a written invitation from Alkan to participate in a repeat performance of the Beethoven Seventh Symphony arrangement at Erard's on 1 March 1843. Late in 1844, Charles Hallé visited Chopin and found him "hardly able to move, bent like a half-opened penknife and evidently in great pain", although his spirits returned when he started to play the piano for his visitor. Chopin's health continued to deteriorate, particularly from this time onwards. Modern research suggests that apart from any other illnesses, he may also have suffered from temporal lobe epilepsy.

Answer:
repeat performance of the Beethoven Seventh Symphony