Extract the answer to the question from the following context. Question: How were the rpms originally determined? Context: In 1925, 78.26 rpm was chosen as the standard because of the introduction of the electrically powered synchronous turntable motor. This motor ran at 3600 rpm, such that a 46:1 gear ratio would produce 78.26 rpm. In parts of the world that used 50 Hz current, the standard was 77.92 rpm (3,000 rpm with a 77:2 ratio), which was also the speed at which a strobe disc with 77 lines would "stand still" in 50 Hz light (92 lines for 60 Hz). After World War II these records were retroactively known as 78s, to distinguish them from other newer disc record formats. Earlier they were just called records, or when there was a need to distinguish them from cylinders, disc records.
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Answer: the electrically powered synchronous turntable motor

Extract the answer to the question from the following context. Question: Which of the following is not a historical period: Han or Qiu? Context: By the late Eastern Han period, an early form of semi-cursive script appeared, developing out of a cursively written form of neo-clerical script[c] and simple cursive. This semi-cursive script was traditionally attributed to Liu Desheng c. 147188 AD,[d] although such attributions refer to early masters of a script rather than to their actual inventors, since the scripts generally evolved into being over time. Qiu gives examples of early semi-cursive script, showing that it had popular origins rather than being purely Liu's invention.
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Answer: Qiu

Extract the answer to the question from the following context. Question: What OS doesn't need to sideload apps? Context: Retail versions of Windows 8 are only able to install these apps through Windows Storea namesake distribution platform which offers both apps, and listings for desktop programs certified for comparability with Windows 8. A method to sideload apps from outside Windows Store is available to devices running Windows 8 Enterprise and joined to a domain; Windows 8 Pro and Windows RT devices that are not part of a domain can also sideload apps, but only after special product keys are obtained through volume licensing.
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Answer:
Retail versions of Windows 8