Problem: Electric motor:

Found in applications as diverse as industrial fans, blowers and pumps, machine tools, household appliances, power tools, and disk drives, electric motors can be powered by direct current (DC) sources, such as from batteries, motor vehicles or rectifiers, or by alternating current (AC) sources, such as from the power grid, inverters or generators. Small motors may be found in electric watches. General-purpose motors with highly standardized dimensions and characteristics provide convenient mechanical power for industrial use. The largest of electric motors are used for ship propulsion, pipeline compression and pumped-storage applications with ratings reaching 100 megawatts. Electric motors may be classified by electric power source type, internal construction, application, type of motion output, and so on.

 What does EC stand for?
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A: unanswerable


Problem: History of science:

In Hellenistic Egypt, the mathematician Euclid laid down the foundations of mathematical rigor and introduced the concepts of definition, axiom, theorem and proof still in use today in his Elements, considered the most influential textbook ever written. Archimedes, considered one of the greatest mathematicians of all time, is credited with using the method of exhaustion to calculate the area under the arc of a parabola with the summation of an infinite series, and gave a remarkably accurate approximation of Pi. He is also known in physics for laying the foundations of hydrostatics, statics, and the explanation of the principle of the lever.

What method did Archimedes employ to determine the area under a parabola?
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A: exhaustion


Problem: Portugal:

Pelayos' plan was to use the Cantabrian mountains as a place of refuge and protection from the invading Moors. He then aimed to regroup the Iberian Peninsula's Christian armies and use the Cantabrian mountains as a springboard from which to regain their lands from the Moors. In the process, after defeating the Moors in the Battle of Covadonga in 722 AD, Pelayos was proclaimed king, thus founding the Christian Kingdom of Asturias and starting the war of Christian reconquest known in Portuguese as the Reconquista Cristã.

What was Pelayos' plan?
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A: to use the Cantabrian mountains as a place of refuge and protection from the invading Moors


Problem: Cardinal (Catholicism):

Cardinals have in canon law a "privilege of forum" (i.e., exemption from being judged by ecclesiastical tribunals of ordinary rank): only the pope is competent to judge them in matters subject to ecclesiastical jurisdiction (cases that refer to matters that are spiritual or linked with the spiritual, or with regard to infringement of ecclesiastical laws and whatever contains an element of sin, where culpability must be determined and the appropriate ecclesiastical penalty imposed). The pope either decides the case himself or delegates the decision to a tribunal, usually one of the tribunals or congregations of the Roman Curia. Without such delegation, no ecclesiastical court, even the Roman Rota, is competent to judge a canon law case against a cardinal. Cardinals are, however, subject to the civil and criminal law like everybody else.

What does the privilege of democracy guarantee cardinals and popes?
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A:
unanswerable