Problem: Late Middle Ages:

The ideas of the Italian Renaissance were slow to cross the Alps into northern Europe, but important artistic innovations were made also in the Low Countries. Though not – as previously believed – the inventor of oil painting, Jan van Eyck was a champion of the new medium, and used it to create works of great realism and minute detail. The two cultures influenced each other and learned from each other, but painting in the Netherlands remained more focused on textures and surfaces than the idealized compositions of Italy.

What painter wasn't an early champion of oil as a medium in painting?
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A: unanswerable


Problem: The Xinhai Revolution led to the founding of the Republic of China in January 1912 with Sun Yat-sen as the first provisional president and Nanking was selected as its new capital. However, the Qing Empire controlled large regions to the north, so revolutionaries asked Yuan Shikai to replace Sun as president in exchange for the abdication of Puyi, the Last Emperor. Yuan demanded the capital be Beijing (closer to his power base).
Who moved the capital from Nanjing to Beijing?
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Answer: Yuan Shikai


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
However, excessive hunting and poachers have also contributed heavily to the endangerment, extirpation and extinction of many animals, such as the quagga, the great auk, Steller's sea cow, the thylacine, the bluebuck, the Arabian oryx, the Caspian and Javan tigers, the markhor, the Sumatran rhinoceros, the bison, the North American cougar, the Altai argali sheep, the Asian elephant and many more, primarily for commercial sale or sport. All these animals have been hunted to endangerment or extinction.
What is the main predator of the quagga?
A: unanswerable


Context and question: The power to review the constitutionality of laws may be limited by Congress, which has the power to set the jurisdiction of the courts. The only constitutional limit on Congress' power to set the jurisdiction of the judiciary relates to the Supreme Court; the Supreme Court may exercise only appellate jurisdiction except in cases involving states and cases affecting foreign ambassadors, ministers or consuls.
Who can limit judicial review of a law?
Answer: Congress


Question: An advantage of the universal motor is that AC supplies may be used on motors which have some characteristics more common in DC motors, specifically high starting torque and very compact design if high running speeds are used. The negative aspect is the maintenance and short life problems caused by the commutator. Such motors are used in devices such as food mixers and power tools which are used only intermittently, and often have high starting-torque demands. Multiple taps on the field coil provide (imprecise) stepped speed control. Household blenders that advertise many speeds frequently combine a field coil with several taps and a diode that can be inserted in series with the motor (causing the motor to run on half-wave rectified AC). Universal motors also lend themselves to electronic speed control and, as such, are an ideal choice for devices like domestic washing machines. The motor can be used to agitate the drum (both forwards and in reverse) by switching the field winding with respect to the armature.
Is there an answer to this question: How is stepped speed control achieved?

Answer: Multiple taps on the field coil provide


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Roman Catholics believe in the Immaculate Conception of Mary, as proclaimed Ex Cathedra by Pope Pius IX in 1854, namely that she was filled with grace from the very moment of her conception in her mother's womb and preserved from the stain of original sin. The Latin Rite of the Roman Catholic Church has a liturgical feast by that name, kept on December 8. Orthodox Christians reject the Immaculate Conception dogma principally because their understanding of ancestral sin (the Greek term corresponding to the Latin "original sin") differs from the Augustinian interpretation and that of the Roman Catholic Church.
In what year did Orthodox Christians reject the Ex Cathedra?
A:
unanswerable