Problem: History of science:

The scientific revolution is a convenient boundary between ancient thought and classical physics. Nicolaus Copernicus revived the heliocentric model of the solar system described by Aristarchus of Samos. This was followed by the first known model of planetary motion given by Johannes Kepler in the early 17th century, which proposed that the planets follow elliptical orbits, with the Sun at one focus of the ellipse. Galileo ("Father of Modern Physics") also made use of experiments to validate physical theories, a key element of the scientific method.

Johannes Kepler created a model of what?
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A: planetary motion

Problem: Liberia:

The Kpelle comprise more than 20% of the population and are the largest ethnic group in Liberia, residing mostly in Bong County and adjacent areas in central Liberia. Americo-Liberians, who are descendants of African American and West Indian, mostly Barbadian settlers, make up 2.5%. Congo people, descendants of repatriated Congo and Afro-Caribbean slaves who arrived in 1825, make up an estimated 2.5%. These latter two groups established political control in the 19th century which they kept well into the 20th century.

When did the decendents of West Indian settlers arrive in Liberia?
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A: unanswerable

Problem: Space Race:

The German rocket center in Peenemunde was located in the eastern part of Germany, which became the Soviet zone of occupation. On Stalin's orders, the Soviet Union sent its best rocket engineers to this region to see what they could salvage for future weapons systems. The Soviet rocket engineers were led by Sergei Korolev. He had been involved in space clubs and early Soviet rocket design in the 1930s, but was arrested in 1938 during Joseph Stalin's Great Purge and imprisoned for six years in Siberia. After the war, he became the USSR's chief rocket and spacecraft engineer, essentially the Soviet counterpart to von Braun. His identity was kept a state secret throughout the Cold War, and he was identified publicly only as "the Chief Designer." In the West, his name was only officially revealed when he died in 1966.

Who was in charge of the Soviet rocket engineer team that went into Germany?
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A: Sergei Korolev

Problem: Pain:

In 1994, responding to the need for a more useful system for describing chronic pain, the International Association for the Study of Pain (IASP) classified pain according to specific characteristics: (1) region of the body involved (e.g. abdomen, lower limbs), (2) system whose dysfunction may be causing the pain (e.g., nervous, gastrointestinal), (3) duration and pattern of occurrence, (4) intensity and time since onset, and (5) etiology. However, this system has been criticized by Clifford J. Woolf and others as inadequate for guiding research and treatment. Woolf suggests three classes of pain : (1) nociceptive pain, (2) inflammatory pain which is associated with tissue damage and the infiltration of immune cells, and (3) pathological pain which is a disease state caused by damage to the nervous system or by its abnormal function (e.g. fibromyalgia, irritable bowel syndrome, tension type headache, etc.).

What is the definition of pathological dysfunction?
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A:
unanswerable