Problem: House music:

Rachel Cain, co-founder of an influential Trax Records, was previously involved in the burgeoning punk scene and cites industrial and post-punk record store Wax Trax! Records as an important connection between the ever-changing underground sounds of Chicago. As most proto-house DJs were primarily stuck to playing their conventional ensemble of dance records, Frankie Knuckles and Ron Hardy, two influential pioneers of house music, were known for their out-of-bounds behavior. The former, credited as "the Godfather of House," worked primarily with early disco music with a hint of new and different music (whether it was post-punk or post-disco) but still enjoying a variety of music, while the latter produced unconventional DIY mixtapes which he later played straight-on in the music club Muzic Box, boiling with raw energy. Marshall Jefferson, who would later appear with the Chicago house classic "Move Your Body (The House-Music Anthem)," (originally released on Chicago-based Trax Records) got involved in house music after hearing Ron Hardy's music in Muzic Box.

marshall jefferson got involved in house music after hearing whose music?
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A: Ron Hardy's

Problem: The British adopted "effective ceiling", meaning the altitude at which a gun could deliver a series of shells against a moving target; this could be constrained by maximum fuse running time as well as the gun's capability. By the late 1930s the British definition was "that height at which a directly approaching target at 400 mph (=643.6 km/h) can be engaged for 20 seconds before the gun reaches 70 degrees elevation". However, effective ceiling for heavy AA guns was affected by non-ballistic factors:
What term is used to describe the altitude for a gun to shoot shells against a target that is moving?
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Answer: "effective ceiling"

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
In 1870, Charles Taze Russell and others formed a group in Pittsburgh, Pennsylvania, to study the Bible. During the course of his ministry, Russell disputed many beliefs of mainstream Christianity including immortality of the soul, hellfire, predestination, the fleshly return of Jesus Christ, the Trinity, and the burning up of the world. In 1876, Russell met Nelson H. Barbour; later that year they jointly produced the book Three Worlds, which combined restitutionist views with end time prophecy. The book taught that God's dealings with humanity were divided dispensationally, each ending with a "harvest," that Christ had returned as an invisible spirit being in 1874 inaugurating the "harvest of the Gospel age," and that 1914 would mark the end of a 2520-year period called "the Gentile Times," at which time world society would be replaced by the full establishment of God's kingdom on earth. Beginning in 1878 Russell and Barbour jointly edited a religious journal, Herald of the Morning. In June 1879 the two split over doctrinal differences, and in July, Russell began publishing the magazine Zion's Watch Tower and Herald of Christ's Presence, stating that its purpose was to demonstrate that the world was in "the last days," and that a new age of earthly and human restitution under the reign of Christ was imminent.
What was the name of a member in Charles Taze Russell's group in 1870?
A: unanswerable

Context and question: RIBA runs many awards including the Stirling Prize for the best new building of the year, the Royal Gold Medal (first awarded in 1848), which honours a distinguished body of work, and the Stephen Lawrence Prize for projects with a construction budget of less than 500,000. The RIBA also awards the President's Medals for student work, which are regarded as the most prestigious awards in architectural education, and the RIBA President's Awards for Research. The RIBA European Award was inaugurated in 2005 for work in the European Union, outside the UK. The RIBA National Award and the RIBA International Award were established in 2007. Since 1966, the RIBA also judges regional awards which are presented locally in the UK regions (East, East Midlands, London, North East, North West, Northern Ireland, Scotland, South/South East, South West/Wessex, Wales, West Midlands and Yorkshire).
What does the Royal Institute of British Architects award the Stirling Prize for?
Answer: the best new building of the year

Question: The Namibian Constitution adopted in February 1990 incorporated protection for human rights, compensation for state expropriations of private property, an independent judiciary and an executive presidency (the constituent assembly became the national assembly). The country officially became independent on 21 March 1990. Sam Nujoma was sworn in as the first President of Namibia watched by Nelson Mandela (who had been released from prison the previous month) and representatives from 147 countries, including 20 heads of state. Walvis Bay was ceded to Namibia in 1994 upon the end of Apartheid in South Africa.[citation needed]
Is there an answer to this question: In what month and year did Namibian leaders start to develop their constitution?

Answer: unanswerable

QUES: In Chapter II, Darwin specifies that the distinction between species and varieties is arbitrary, with experts disagreeing and changing their decisions when new forms were found. He concludes that "a well-marked variety may be justly called an incipient species" and that "species are only strongly marked and permanent varieties". He argues for the ubiquity of variation in nature. Historians have noted that naturalists had long been aware that the individuals of a species differed from one another, but had generally considered such variations to be limited and unimportant deviations from the archetype of each species, that archetype being a fixed ideal in the mind of God. Darwin and Wallace made variation among individuals of the same species central to understanding the natural world.

What did Darwin and Wallace make central to understanding the natural world?
What is the answer?
ANS:
variation among individuals of the same species