Problem: Estonian language:

During the Perestroika era, The Law on the Status of the Estonian Language was adopted in January 1989. The collapse of the Soviet Union led to the restoration of Republic of Estonia's independence. Estonian went back to being the only state language in Estonia which in practice meant that use of Estonian was promoted while the use of Russian was discouraged.

When was Russian encouraged to be used in Estonia?
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A: unanswerable


Problem: United States Air Force:

The United States Air Force (USAF) is the aerial warfare service branch of the United States Armed Forces and one of the seven American uniformed services. Initially part of the United States Army, the USAF was formed as a separate branch of the military on 18 September 1947 under the National Security Act of 1947. It is the most recent branch of the U.S. military to be formed, and is the largest and one of the world's most technologically advanced air forces. The USAF articulates its core functions as Nuclear Deterrence Operations, Special Operations, Air Superiority, Global Integrated ISR, Space Superiority, Command and Control, Cyberspace Superiority, Personnel Recovery, Global Precision Attack, Building Partnerships, Rapid Global Mobility and Agile Combat Support.

What act formed the USAF?
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A: National Security Act of 1947


Problem: New York City:

The Staten Island Railway rapid transit system solely serves Staten Island, operating 24 hours a day. The Port Authority Trans-Hudson (PATH train) links Midtown and Lower Manhattan to northeastern New Jersey, primarily Hoboken, Jersey City, and Newark. Like the New York City Subway, the PATH operates 24 hours a day; meaning three of the six rapid transit systems in the world which operate on 24-hour schedules are wholly or partly in New York (the others are a portion of the Chicago 'L', the PATCO Speedline serving Philadelphia, and the Copenhagen Metro).

How many 24-hour rapid transit systems are located in New York?
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A: three


Problem: Kievan Rus%27:

After the Rus' attack on Constantinople in 860, the Byzantine Patriarch Photius sent missionaries north to convert the Rus' and the Slavs. Prince Rastislav of Moravia had requested the Emperor to provide teachers to interpret the holy scriptures, so in 863 the brothers Cyril and Methodius were sent as missionaries, due to their knowledge of the Slavonic language. The Slavs had no written language, so the brothers devised the Glagolitic alphabet, later developed into Cyrillic, and standardized the language of the Slavs, later known as Old Church Slavonic. They translated portions of the Bible and drafted the first Slavic civil code and other documents, and the language and texts spread throughout Slavic territories, including Kievan Rus’. The mission of Cyril and Methodius served both evangelical and diplomatic purposes, spreading Byzantine cultural influence in support of imperial foreign policy. In 867 the Patriarch announced that the Rus' had accepted a bishop, and in 874 he speaks of an "Archbishop of the Rus'."

What had Prince Rastislav requested?
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A:
provide teachers