Problem: Slavs:

The Slavs under name of the Antes and the Sclaveni make their first appearance in Byzantine records in the early 6th century. Byzantine historiographers under Justinian I (527565), such as Procopius of Caesarea, Jordanes and Theophylact Simocatta describe tribes of these names emerging from the area of the Carpathian Mountains, the lower Danube and the Black Sea, invading the Danubian provinces of the Eastern Empire.

What was another name for Byzantine?
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A: unanswerable

Problem: Classical music:

European art music is largely distinguished from many other non-European and popular musical forms by its system of staff notation, in use since about the 16th century. Western staff notation is used by composers to prescribe to the performer the pitches (e.g., melodies, basslines and/or chords), tempo, meter and rhythms for a piece of music. This leaves less room for practices such as improvisation and ad libitum ornamentation, which are frequently heard in non-European art music and in popular music styles such as jazz and blues. Another difference is that whereas most popular styles lend themselves to the song form, classical music has been noted for its development of highly sophisticated forms of instrumental music such as the concerto, symphony, sonata, and mixed vocal and instrumental styles such as opera which, since they are written down, can attain a high level of complexity.

Jazz and blues use ad libitum and what other ornamentation?
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A: improvisation

Problem: Alexander Graham Bell:

Although Alexander Graham Bell is most often associated with the invention of the telephone, his interests were extremely varied. According to one of his biographers, Charlotte Gray, Bell's work ranged "unfettered across the scientific landscape" and he often went to bed voraciously reading the Encyclopdia Britannica, scouring it for new areas of interest. The range of Bell's inventive genius is represented only in part by the 18 patents granted in his name alone and the 12 he shared with his collaborators. These included 14 for the telephone and telegraph, four for the photophone, one for the phonograph, five for aerial vehicles, four for "hydroairplanes" and two for selenium cells. Bell's inventions spanned a wide range of interests and included a metal jacket to assist in breathing, the audiometer to detect minor hearing problems, a device to locate icebergs, investigations on how to separate salt from seawater, and work on finding alternative fuels.

What series of books does Gray say Bell would go to sleep reading?
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A: Encyclopdia Britannica

Problem: Lighting:

Light pollution is a growing problem in reaction to excess light being given off by numerous signs, houses, and buildings. Polluting light is often wasted light involving unnecessary energy costs and carbon dioxide emissions. Light pollution is described as artificial light that is excessive or intrudes where it is not wanted. Well-designed lighting sends light only where it is needed without scattering it elsewhere. Poorly designed lighting can also compromise safety. For example, glare creates safety issues around buildings by causing very sharp shadows, temporarily blinding passersby making them vulnerable to would-be assailants.

What is known as artificial light that is excessive or intrusive?
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A:
Light pollution