Problem: Space Race:

On October 2, 1997, it was reported that Khrushchev's son Sergei claimed Khrushchev was poised to accept Kennedy's proposal at the time of Kennedy's assassination on November 22, 1963. During the next few weeks he reportedly concluded that both nations might realize cost benefits and technological gains from a joint venture, and decided to accept Kennedy's offer based on a measure of rapport during their years as leaders of the world's two superpowers, but changed his mind and dropped the idea since he did not have the same trust for Kennedy's successor, Lyndon Johnson.

How did US President Kennedy die?
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A: assassination

Problem: Serotonin is a neuromodulator involved in regulation of mood and behavior. Development in the limbic system plays an important role in determining rewards and punishments and processing emotional experience and social information. Changes in the levels of the neurotransmitters dopamine and serotonin in the limbic system make adolescents more emotional and more responsive to rewards and stress. The corresponding increase in emotional variability also can increase adolescents' vulnerability. The effect of serotonin is not limited to the limbic system: Several serotonin receptors have their gene expression change dramatically during adolescence, particularly in the human frontal and prefrontal cortex .
Serotonin is a neuromodulator that is involved in regulation of what?
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Answer: mood and behavior

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The first phase of Eddy Street Commons, a $215 million development located adjacent to the University of Notre Dame campus and funded by the university, broke ground on June 3, 2008. The Eddy Street Commons drew union protests when workers hired by the City of South Bend to construct the public parking garage picketed the private work site after a contractor hired non-union workers. The developer, Kite Realty out of Indianapolis, has made agreements with major national chains rather than local businesses, a move that has led to criticism from alumni and students.
Which entity did Notre Dame hire to build a parking structure outside of Eddy Street Commons?
A: the City of South Bend

Context and question: Egypt has one of the longest histories of any modern country, arising in the tenth millennium BC as one of the world's first nation states. Considered a cradle of civilisation, Ancient Egypt experienced some of the earliest developments of writing, agriculture, urbanisation, organised religion and central government. Iconic monuments such as the Giza Necropolis and its Great Sphinx, as well the ruins of Memphis, Thebes, Karnak, and the Valley of the Kings, reflect this legacy and remain a significant focus of archaeological study and popular interest worldwide. Egypt's rich cultural heritage is an integral part of its national identity, having endured, and at times assimilated, various foreign influences, including Greek, Persian, Roman, Arab, Ottoman, and European. Although Christianised in the first century of the Common Era, it was subsequently Islamised due to the Islamic conquests of the seventh century.
In what century were islamic conquests of Egypt?
Answer: seventh century

Question: One significant feature of the Premier League in the mid-2000s was the dominance of the so-called "Big Four" clubs: Arsenal, Chelsea, Liverpool and Manchester United. During this decade, and particularly from 2002 to 2009, they dominated the top four spots, which came with UEFA Champions League qualification, taking all top four places in 5 out of 6 seasons from 200304 to 200809 inclusive, with Arsenal going as far as winning the league without losing a single game in 200304, the only time it has ever happened in the Premier League. In May 2008 Kevin Keegan stated that "Big Four" dominance threatened the division, "This league is in danger of becoming one of the most boring but great leagues in the world." Premier League chief executive Richard Scudamore said in defence: "There are a lot of different tussles that go on in the Premier League depending on whether you're at the top, in the middle or at the bottom that make it interesting."
Is there an answer to this question: Which of the "Big Four" teams did not lose a single game in the 2003-04 season?

Answer: Arsenal

Problem: Mandolin:

The second decline was not as complete as the first. Thousands of people had learned to play the instrument. Even as the second wave of mandolin popularity declined in the early 20th century, new versions of the mandolin began to be used in new forms of music. Luthiers created the resonator mandolin, the flatback mandolin, the carved-top or arched-top mandolin, the mandolin-banjo and the electric mandolin. Musicians began playing it in Celtic, Bluegrass, Jazz and Rock-n-Roll styles and Classical too.

When did the first wave of mandolin popularity decline?
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A:
unanswerable