In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

What happened in the lower part of the country?, Context: 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.
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

What is one example of hydrogen cations?, Context: To avoid the implication of the naked "solvated proton" in solution, acidic aqueous solutions are sometimes considered to contain a less unlikely fictitious species, termed the "hydronium ion" (H3O+). However, even in this case, such solvated hydrogen cations are more realistically conceived as being organized into clusters that form species closer to H9O+4. Other oxonium ions are found when water is in acidic solution with other solvents.
hydronium ion

Why did the academic pursuits of science come into being?, Context: Scientific academies and societies grew out of the Scientific Revolution as the creators of scientific knowledge in contrast to the scholasticism of the university. During the Enlightenment, some societies created or retained links to universities. However, contemporary sources distinguished universities from scientific societies by claiming that the university's utility was in the transmission of knowledge, while societies functioned to create knowledge. As the role of universities in institutionalized science began to diminish, learned societies became the cornerstone of organized science. Official scientific societies were chartered by the state in order to provide technical expertise. Most societies were granted permission to oversee their own publications, control the election of new members, and the administration of the society. After 1700, a tremendous number of official academies and societies were founded in Europe, and by 1789 there were over seventy official scientific societies. In reference to this growth, Bernard de Fontenelle coined the term "the Age of Academies" to describe the 18th century.

Scientific Revolution