Problem: Time:

Time is one of the seven fundamental physical quantities in both the International System of Units and International System of Quantities. Time is used to define other quantities—such as velocity—so defining time in terms of such quantities would result in circularity of definition. An operational definition of time, wherein one says that observing a certain number of repetitions of one or another standard cyclical event (such as the passage of a free-swinging pendulum) constitutes one standard unit such as the second, is highly useful in the conduct of both advanced experiments and everyday affairs of life. The operational definition leaves aside the question whether there is something called time, apart from the counting activity just mentioned, that flows and that can be measured. Investigations of a single continuum called spacetime bring questions about space into questions about time, questions that have their roots in the works of early students of natural philosophy.

Philosophy is one of the fundamental physical quantities in which two systems?
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A: unanswerable


Problem: Slavs:

In the 7th century, the Frankish merchant Samo, who supported the Slavs fighting their Avar rulers, became the ruler of the first known Slav state in Central Europe, which, however, most probably did not outlive its founder and ruler. This provided the foundation for subsequent Slavic states to arise on the former territory of this realm with Carantania being the oldest of them. Very old also are the Principality of Nitra and the Moravian principality (see under Great Moravia). In this period, there existed central Slavic groups and states such as the Balaton Principality, but the subsequent expansion of the Magyars, as well as the Germanisation of Austria, separated the northern and southern Slavs. The First Bulgarian Empire was founded in 681, the Slavic language Old Bulgarian became the main and official of the empire in 864. Bulgaria was instrumental in the spread of Slavic literacy and Christianity to the rest of the Slavic world.

Bulgaria was instrumental in the spread of what to the rest of the Slavic world?
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A: Slavic literacy and Christianity


Problem: A cappella:

The reasons for the strong Swedish dominance are as explained by Richard Sparks manifold; suffice to say here that there is a long-standing tradition, an unsusually large proportion of the populations (5% is often cited) regularly sing in choirs, the Swedish choral director Eric Ericson had an enormous impact on a cappella choral development not only in Sweden but around the world, and finally there are a large number of very popular primary and secondary schools (music schools) with high admission standards based on auditions that combine a rigid academic regimen with high level choral singing on every school day, a system that started with Adolf Fredrik's Music School in Stockholm in 1939 but has spread over the country.

What portion of the Swedish population engages in a cappella singing?
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A: 5%


Problem: Valencia:

During the Cantonal Revolution of 1873, a cantonalist uprising that took place during the First Spanish Republic, the city was consolidated with most of the nearby cities in the Federal Canton of Valencia (proclaimed on 19 July and dissolved on 7 August). It did not have the revolutionary fervor of the movement in cities like Alcoy, as it was initiated by the bourgeoisie, but the Madrid government sent General Martinez-Campos to stifle the rebellion by force of arms and subjected Valencia to an intense bombardment. The city surrendered on 7 August; Alfonso XII was proclaimed king on 29 December 1874, and arrived in Valencia on 11 January 1875 on his way to Madrid, marking the end of the first republic. Despite the Bourbon restoration, the roughly even balance between conservatives and liberals in the government was sustained in Valencia until the granting of universal male suffrage in 1890, after which the Republicans, led by Vicente Blasco Ibáñez, gained considerably more of the popular vote.

Who was sent to stop Valencia's uprising?
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A:
General Martinez-Campos