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Elevators with more than 30 m (98 ft) of travel have a system called compensation. This is a separate set of cables or a chain attached to the bottom of the counterweight and the bottom of the elevator cab. This makes it easier to control the elevator, as it compensates for the differing weight of cable between the hoist and the cab. If the elevator cab is at the top of the hoist-way, there is a short length of hoist cable above the car and a long length of compensating cable below the car and vice versa for the counterweight. If the compensation system uses cables, there will be an additional sheave in the pit below the elevator, to guide the cables. If the compensation system uses chains, the chain is guided by a bar mounted between the counterweight railway lines.
"Compensation" is the name of the system used for what type of elevators?
A: Elevators with more than 30 m (98 ft) of travel

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Glass is in widespread use largely due to the production of glass compositions that are transparent to visible light. In contrast, polycrystalline materials do not generally transmit visible light. The individual crystallites may be transparent, but their facets (grain boundaries) reflect or scatter light resulting in diffuse reflection. Glass does not contain the internal subdivisions associated with grain boundaries in polycrystals and hence does not scatter light in the same manner as a polycrystalline material. The surface of a glass is often smooth since during glass formation the molecules of the supercooled liquid are not forced to dispose in rigid crystal geometries and can follow surface tension, which imposes a microscopically smooth surface. These properties, which give glass its clearness, can be retained even if glass is partially light-absorbing—i.e., colored.
What type of glass absorbs some light?
A: colored

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Kievan Rus' also played an important genealogical role in European politics. Yaroslav the Wise, whose stepmother belonged to the Macedonian dynasty, the greatest one to rule Byzantium, married the only legitimate daughter of the king who Christianized Sweden. His daughters became queens of Hungary, France and Norway, his sons married the daughters of a Polish king and a Byzantine emperor (not to mention a niece of the Pope), while his granddaughters were a German Empress and (according to one theory) the queen of Scotland. A grandson married the only daughter of the last Anglo-Saxon king of England. Thus the Rurikids were a well-connected royal family of the time.
To which dynasty did Yarolav's step mother belong to?
A: Macedonian dynasty

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Around 1300, centuries of prosperity and growth in Europe came to a halt. A series of famines and plagues, including the Great Famine of 1315–1317 and the Black Death, reduced the population to around half of what it was before the calamities. Along with depopulation came social unrest and endemic warfare. France and England experienced serious peasant uprisings, such as the Jacquerie and the Peasants' Revolt, as well as over a century of intermittent conflict in the Hundred Years' War. To add to the many problems of the period, the unity of the Catholic Church was shattered by the Western Schism. Collectively these events are sometimes called the Crisis of the Late Middle Ages.
Which two countries never experienced peasant uprisings?
A:
unanswerable