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: Who was NOT president of SCEA: Hirai or Tretton?, Context: PlayStation Plus (commonly abbreviated PS+ and occasionally referred to as PSN Plus) is a premium PlayStation Network subscription service that was officially unveiled at E3 2010 by Jack Tretton, President and CEO of SCEA. Rumors of such service had been in speculation since Kaz Hirai's announcement at TGS 2009 of a possible paid service for PSN but with the current PSN service still available. Launched alongside PS3 firmware 3.40 and PSP firmware 6.30 on June 29, 2010, the paid-for subscription service provides users with enhanced services on the PlayStation Network, on top of the current PSN service which is still available with all of its features. These enhancements include the ability to have demos, game and system software updates download automatically to PlayStation 3. Subscribers also get early or exclusive access to some betas, game demos, premium downloadable content and other PlayStation Store items. North American users also get a free subscription to Qore. Users may choose to purchase either a one-year or a three-month subscription to PlayStation Plus.

Answer: Hirai


Question: What was the result of correctly sheathing a record?, Context: Vinyl records can be warped by heat, improper storage, exposure to sunlight, or manufacturing defects such as excessively tight plastic shrinkwrap on the album cover. A small degree of warp was common, and allowing for it was part of the art of turntable and tonearm design. "wow" (once-per-revolution pitch variation) could result from warp, or from a spindle hole that was not precisely centered. Standard practice for LPs was to place the LP in a paper or plastic inner cover. This, if placed within the outer cardboard cover so that the opening was entirely within the outer cover, was said to reduce ingress of dust onto the record surface. Singles, with rare exceptions, had simple paper covers with no inner cover.

Answer:
reduce ingress of dust onto the record surface