Please answer this: Extract the answer to the question from the following context. Question: What does PM in PM2.5 stand for? Context: A dense wave of smog began in the Central and Eastern part of China on 2 December 2013 across a distance of around 1,200 kilometres (750 mi), including Tianjin, Hebei, Shandong, Jiangsu, Anhui, Shanghai and Zhejiang. A lack of cold air flow, combined with slow-moving air masses carrying industrial emissions, collected airborne pollutants to form a thick layer of smog over the region. The heavy smog heavily polluted central and southern Jiangsu Province, especially in and around Nanjing, with its AQI pollution Index at "severely polluted" for five straight days and "heavily polluted" for nine. On 3 December 2013, levels of PM2.5 particulate matter average over 943 micrograms per cubic metre, falling to over 338 micrograms per cubic metre on 4 December 2013. Between 3:00 pm, 3 December and 2:00pm, 4 December local time, several expressways from Nanjing to other Jiangsu cities were closed, stranding dozens of passenger buses in Zhongyangmen bus station. From 5 to 6 December, Nanjing issued a red alert for air pollution and closed down all kindergarten through middle schools. Children's Hospital outpatient services increased by 33 percent; general incidence of bronchitis, pneumonia, upper respiratory tract infections significantly increased. The smog dissipated 12 December. Officials blamed the dense pollution on lack of wind, automobile exhaust emissions under low air pressure, and coal-powered district heating system in North China region. Prevailing winds blew low-hanging air masses of factory emissions (mostly SO2) towards China's east coast.
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Answer: particulate matter


Please answer this: Extract the answer to the question from the following context. Question: Popper advocated for what, not qualitative, in determining truth? Context: Upon this basis, along with that of the logical content of assertions (where logical content is inversely proportional to probability), Popper went on to develop his important notion of verisimilitude or "truthlikeness". The intuitive idea behind verisimilitude is that the assertions or hypotheses of scientific theories can be objectively measured with respect to the amount of truth and falsity that they imply. And, in this way, one theory can be evaluated as more or less true than another on a quantitative basis which, Popper emphasises forcefully, has nothing to do with "subjective probabilities" or other merely "epistemic" considerations.
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Answer: quantitative


Please answer this: Extract the answer to the question from the following context. Question: What was happening as the Greeks fled Asia? Context: In the aftermath of the First World War, Greece attempted further expansion into Asia Minor, a region with a large native Greek population at the time, but was defeated in the Greco-Turkish War of 1919–1922, contributing to a massive flight of Asia Minor Greeks. These events overlapped, with both happening during the Greek genocide (1914-1922), a period during which, according to various sources, Ottoman and Turkish officials contributed to the death of several hundred thousand Asia Minor Greeks. The resultant Greek exodus from Asia Minor was made permanent, and expanded, in an official Population exchange between Greece and Turkey. The exchange was part of the terms of the Treaty of Lausanne which ended the war.
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Answer:
Greek genocide