Problem: Josip Broz Tito:

On 12 September 1944, King Peter II called on all Yugoslavs to come together under Tito's leadership and stated that those who did not were "traitors", by which time Tito was recognized by all Allied authorities (including the government-in-exile) as the Prime Minister of Yugoslavia, in addition to commander-in-chief of the Yugoslav forces. On 28 September 1944, the Telegraph Agency of the Soviet Union (TASS) reported that Tito signed an agreement with the Soviet Union allowing "temporary entry" of Soviet troops into Yugoslav territory which allowed the Red Army to assist in operations in the northeastern areas of Yugoslavia. With their strategic right flank secured by the Allied advance, the Partisans prepared and executed a massive general offensive which succeeded in breaking through German lines and forcing a retreat beyond Yugoslav borders. After the Partisan victory and the end of hostilities in Europe, all external forces were ordered off Yugoslav territory.

Who were allowed "temporary entry" into Yugoslav territory?
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A: Soviet troops


Problem: Russian language:

In Ukraine, Russian is seen as a language of inter-ethnic communication, and a minority language, under the 1996 Constitution of Ukraine. According to estimates from Demoskop Weekly, in 2004 there were 14,400,000 native speakers of Russian in the country, and 29 million active speakers. 65% of the population was fluent in Russian in 2006, and 38% used it as the main language with family, friends or at work. Russian is spoken by 29.6% of the population according to a 2001 estimate from the World Factbook. 20% of school students receive their education primarily in Russian.

How many Ukrainians speak Russian natively as of 2004?
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A: 14,400,000


Problem: 2008 Sichuan earthquake:

All of the highways into Wenchuan, and others throughout the province, were damaged, resulting in delayed arrival of the rescue troops. In Beichuan County, 80% of the buildings collapsed according to Xinhua News. In the city of Shifang, the collapse of two chemical plants led to leakage of some 80 tons of liquid ammonia, with hundreds of people reported buried. In the city of Dujiangyan, south-east of the epicenter, a whole school collapsed with 900 students buried and fewer than 60 survived. The Juyuan Middle School, where many teenagers were buried, was excavated by civilians and cranes. Dujiangyan is home of the Dujiangyan Irrigation System, an ancient water diversion project which is still in use and is a UNESCO World Heritage Site. The project's famous Fish Mouth was cracked but not severely damaged otherwise.

What did the damaged roadways cause to the rescue operations?
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A: delayed arrival


Problem: Asphalt:

Canadian bitumen does not differ substantially from oils such as Venezuelan extra-heavy and Mexican heavy oil in chemical composition, and the real difficulty is moving the extremely viscous bitumen through oil pipelines to the refinery. Many modern oil refineries are extremely sophisticated and can process non-upgraded bitumen directly into products such as gasoline, diesel fuel, and refined asphalt without any preprocessing. This is particularly common in areas such as the US Gulf coast, where refineries were designed to process Venezuelan and Mexican oil, and in areas such as the US Midwest where refineries were rebuilt to process heavy oil as domestic light oil production declined. Given the choice, such heavy oil refineries usually prefer to buy bitumen rather than synthetic oil because the cost is lower, and in some cases because they prefer to produce more diesel fuel and less gasoline. By 2015 Canadian production and exports of non-upgraded bitumen exceeded that of synthetic crude oil at over 1.3 million barrels (210×10^3 m3) per day, of which about 65% was exported to the United States.

What property of bitumen makes it difficult to move through pipelines?
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A:
extremely viscous