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High-voltage AC overhead systems are not only for standard gauge national networks. The meter gauge Rhaetian Railway (RhB) and the neighbouring Matterhorn Gotthard Bahn (MGB) operate on 11 kV at 16.7 Hz frequency. Practice has proven that both Swiss and German 15 kV trains can operate under these lower voltages. The RhB started trials of the 11 kV system in 1913 on the Engadin line (St. Moritz-Scuol/Tarasp). The MGB constituents Furka-Oberalp-Bahn (FO) and Brig-Visp-Zermatt Bahn (BVZ) introduced their electric services in 1941 and 1929 respectively, adopting the already proven RhB system.
The MAB consisted of whom?
A: unanswerable

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In Austria, the Austrian Constitution of 1920 (based on a draft by Hans Kelsen) introduced judicial review of legislative acts for their constitutionality. This function is performed by the Constitutional Court (Verfassungsgerichtshof), which is also charged with the review of administrative acts on whether they violate constitutionally guaranteed rights. Other than that, administrative acts are reviewed by the Administrative Court (Verwaltungsgerichtshof). The Supreme Court (Oberste Gerichtshof (OGH)), stands at the top of Austria's system of "ordinary courts" (ordentliche Gerichte) as the final instance in issues of private law and criminal law.
What is the German word for this constitutional high court?
A: Verfassungsgerichtshof

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After the Marzpanate period (428636), Armenia emerged as the Emirate of Armenia, an autonomous principality within the Arabic Empire, reuniting Armenian lands previously taken by the Byzantine Empire as well. The principality was ruled by the Prince of Armenia, and recognized by the Caliph and the Byzantine Emperor. It was part of the administrative division/emirate Arminiya created by the Arabs, which also included parts of Georgia and Caucasian Albania, and had its center in the Armenian city, Dvin. The Principality of Armenia lasted until 884, when it regained its independence from the weakened Arab Empire under King Ashot I Bagratuni.
When did the Principality of Armenia end?
A: 884

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The study of the Quran and the Hadith thrived in such a scholarly atmosphere. Philosophy, Fiqh and theology (kalaam) were further developed, most noticeably by Avicenna and his opponents. Al-Razi and Al-Farabi had provided methodology and knowledge in medicine and philosophy. Avicenna had access to the great libraries of Balkh, Khwarezm, Gorgan, Rey, Isfahan and Hamadan. Various texts (such as the 'Ahd with Bahmanyar) show that he debated philosophical points with the greatest scholars of the time. Aruzi Samarqandi describes how before Avicenna left Khwarezm he had met Al-Biruni (a famous scientist and astronomer), Abu Nasr Iraqi (a renowned mathematician), Abu Sahl Masihi (a respected philosopher) and Abu al-Khayr Khammar (a great physician).
What was one subject that Avicenna never developed?
A:
unanswerable