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Representatives of the Polish government officially took over the civilian administration of the southern part of East Prussia on 23 May 1945. Subsequently Polish expatriates from Polish lands annexed by the Soviet Union as well as Ukrainians and Lemkos from southern Poland, expelled in Operation Vistula in 1947, were settled in the southern part of East Prussia, now the Polish Warmian-Masurian Voivodeship. In 1950 the Olsztyn Voivodeship counted 689,000 inhabitants, 22.6% of them coming from areas annexed by the Soviet Union, 10% Ukrainians, and 18.5% of them pre-war inhabitants. The remaining pre-war population was treated as Germanized Poles and a policy of re-Polonization was pursued throughout the country Most of these "Autochthones" chose to emigrate to West Germany from the 1950s through 1970s (between 1970 and 1988 55,227 persons from Warmia and Masuria moved to Western Germany). Local toponyms were Polonised by the Polish Commission for the Determination of Place Names.
How many were expelled in Operation Vistula in 1947?
A: unanswerable

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In September 1828 Chopin, while still a student, visited Berlin with a family friend, zoologist Feliks Jarocki, enjoying operas directed by Gaspare Spontini and attending concerts by Carl Friedrich Zelter, Felix Mendelssohn and other celebrities. On an 1829 return trip to Berlin, he was a guest of Prince Antoni Radziwi, governor of the Grand Duchy of Posenhimself an accomplished composer and aspiring cellist. For the prince and his pianist daughter Wanda, he composed his Introduction and Polonaise brillante in C major for cello and piano, Op. 3.
What piece did Chopin create for Prince Antoni?
A: Introduction and Polonaise brillante in C major for cello and piano, Op. 3

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All of Chopin's compositions include the piano. Most are for solo piano, though he also wrote two piano concertos, a few chamber pieces, and some songs to Polish lyrics. His keyboard style is highly individual and often technically demanding; his own performances were noted for their nuance and sensitivity. Chopin invented the concept of instrumental ballade. His major piano works also include mazurkas, waltzes, nocturnes, polonaises, etudes, impromptus, scherzos, preludes and sonatas, some published only after his death. Influences on his compositional style include Polish folk music, the classical tradition of J. S. Bach, Mozart and Schubert, the music of all of whom he admired, as well as the Paris salons where he was a frequent guest. His innovations in style, musical form, and harmony, and his association of music with nationalism, were influential throughout and after the late Romantic period.
What features marked Frederic's performance style and made them unique?
A: nuance and sensitivity

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By the end of May, drafts were formally presented. In mid-June, the main Tripartite negotiations started. The discussion was focused on potential guarantees to central and east European countries should a German aggression arise. The USSR proposed to consider that a political turn towards Germany by the Baltic states would constitute an "indirect aggression" towards the Soviet Union. Britain opposed such proposals, because they feared the Soviets' proposed language could justify a Soviet intervention in Finland and the Baltic states, or push those countries to seek closer relations with Germany. The discussion about a definition of "indirect aggression" became one of the sticking points between the parties, and by mid-July, the tripartite political negotiations effectively stalled, while the parties agreed to start negotiations on a military agreement, which the Soviets insisted must be entered into simultaneously with any political agreement.
What month did the Tripartite discussions begin between Britain, USSR and France?
A:
mid-June