Problem: Electric motor:

The continuous torque density of conventional electric machines is determined by the size of the air-gap area and the back-iron depth, which are determined by the power rating of the armature winding set, the speed of the machine, and the achievable air-gap flux density before core saturation. Despite the high coercivity of neodymium or samarium-cobalt PMs, continuous torque density is virtually the same amongst electric machines with optimally designed armature winding sets. Continuous torque density relates to method of cooling and permissible period of operation before destruction by overheating of windings or PM damage.

What does continuous torque density refer to?
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A: method of cooling and permissible period of operation before destruction by overheating

Problem: Internationally, Sassou's regime has been hit by corruption revelations despite attempts to censor them. One French investigation found over 110 bank accounts and dozens of lavish properties in France; Sassou denounced embezzlement investigations as "racist" and "colonial".
What did France denounce embezzlement investigations as?
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Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
A state's consent may be invalidated if there was an erroneous understanding of a fact or situation at the time of conclusion, which formed the "essential basis" of the state's consent. Consent will not be invalidated if the misunderstanding was due to the state's own conduct, or if the truth should have been evident.
What on behalf of a state cannot invalidate that state's consent to a treaty?
A: own conduct

Context and question: All over Europe rulers and city governments began to create universities to satisfy a European thirst for knowledge, and the belief that society would benefit from the scholarly expertise generated from these institutions. Princes and leaders of city governments perceived the potential benefits of having a scholarly expertise develop with the ability to address difficult problems and achieve desired ends. The emergence of humanism was essential to this understanding of the possible utility of universities as well as the revival of interest in knowledge gained from ancient Greek texts.
Who established unuiversities for their own benefit?
Answer: unanswerable

Question: In 1920, Turkish nationalist forces invaded the fledgling Armenian republic from the east. Turkish forces under the command of Kazm Karabekir captured Armenian territories that Russia had annexed in the aftermath of the 18771878 Russo-Turkish War and occupied the old city of Alexandropol (present-day Gyumri). The violent conflict finally concluded with the Treaty of Alexandropol on 2 December 1920. The treaty forced Armenia to disarm most of its military forces, cede all former Ottoman territory granted to it by the Treaty of Sevres, and to give up all the "Wilsonian Armenia" granted to it at the Sevres treaty. Simultaneously, the Soviet Eleventh Army, under the command of Grigoriy Ordzhonikidze, invaded Armenia at Karavansarai (present-day Ijevan) on 29 November. By 4 December, Ordzhonikidze's forces entered Yerevan and the short-lived Armenian republic collapsed.
Is there an answer to this question: When did the Armenian republic breakdown?

Answer: 4 December

Problem: Slavs:

According to eastern homeland theory, prior to becoming known to the Roman world, Slavic-speaking tribes were part of the many multi-ethnic confederacies of Eurasia such as the Sarmatian, Hun and Gothic empires. The Slavs emerged from obscurity when the westward movement of Germans in the 5th and 6th centuries CE (thought to be in conjunction with the movement of peoples from Siberia and Eastern Europe: Huns, and later Avars and Bulgars) started the great migration of the Slavs, who settled the lands abandoned by Germanic tribes fleeing the Huns and their allies: westward into the country between the Oder and the Elbe-Saale line; southward into Bohemia, Moravia, much of present-day Austria, the Pannonian plain and the Balkans; and northward along the upper Dnieper river. Perhaps some Slavs migrated with the movement of the Vandals to Iberia and north Africa.

What empires were part of the Roman world?
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A:
unanswerable