Problem: Utrecht:

By the mid-7th century, English and Irish missionaries set out to convert the Frisians. The pope appointed their leader, Willibrordus, bishop of the Frisians. The tenure of Willibrordus is generally considered to be the beginning of the Bishopric of Utrecht. In 723, the Frankish leader Charles Martel bestowed the fortress in Utrecht and the surrounding lands as the base of the bishops. From then on Utrecht became one of the most influential seats of power for the Roman Catholic Church in the Netherlands. The archbishops of Utrecht were based at the uneasy northern border of the Carolingian Empire. In addition, the city of Utrecht had competition from the nearby trading centre Dorestad. After the fall of Dorestad around 850, Utrecht became one of the most important cities in the Netherlands. The importance of Utrecht as a centre of Christianity is illustrated by the election of the Utrecht-born Adriaan Florenszoon Boeyens as pope in 1522 (the last non-Italian pope before John Paul II).

What city fell in the 8th century?
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A: unanswerable


Problem: Many scripts, including Arabic and Devanagari, have special orthographic rules that require certain combinations of letterforms to be combined into special ligature forms. The rules governing ligature formation can be quite complex, requiring special script-shaping technologies such as ACE (Arabic Calligraphic Engine by DecoType in the 1980s and used to generate all the Arabic examples in the printed editions of the Unicode Standard), which became the proof of concept for OpenType (by Adobe and Microsoft), Graphite (by SIL International), or AAT (by Apple).
Who created ACE?
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Answer: DecoType


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Mechanically scanned, 30-line television broadcasts by John Logie Baird began in 1929, using the BBC transmitter in London, and by 1930 a regular schedule of programmes was transmitted from the BBC antenna in Brookmans Park. Television production was switched from Baird's company to what is now known as BBC One on 2 August 1932, and continued until September 1935. Regularly scheduled electronically scanned television began from Alexandra Palace in London on 2 November 1936, to just a few hundred viewers in the immediate area. The first programme broadcast – and thus the first ever, on a dedicated TV channel – was "Opening of the BBC Television Service" at 15:00. The first major outside broadcast was the coronation of King George VI and Queen Elizabeth in May 1937. The service was reaching an estimated 25,000–40,000 homes before the outbreak of World War II which caused the service to be suspended in September 1939. The VHF broadcasts would have provided an ideal radio beacon for German bombers homing in on London, and the engineers and technicians of the service would be needed for the war effort, in particular the radar programme.
When did the BBC start broadcasting under the name BBC One?
A: 2 August 1932


Context and question: The United States had multiple rocket programs divided among the different branches of the American armed services, which meant that each force developed its own ICBM program. The Air Force initiated ICBM research in 1945 with the MX-774. However, its funding was cancelled and only three partially successful launches were conducted in 1947. In 1950, von Braun began testing the Air Force PGM-11 Redstone rocket family at Cape Canaveral. In 1951, the Air Force began a new ICBM program called MX-1593, and by 1955 this program was receiving top-priority funding. The MX-1593 program evolved to become the Atlas-A, with its maiden launch occurring June 11, 1957, becoming the first successful American ICBM. Its upgraded version, the Atlas-D rocket, would later serve as an operational nuclear ICBM and as the orbital launch vehicle for Project Mercury and the remote-controlled Agena Target Vehicle used in Project Gemini.
The US Air Force began research of ICBMs in what year?
Answer: 1945


Question: Kuaiji Commandery was the initial power base for Xiang Liang and Xiang Yu's rebellion against the Qin Empire which initially succeeded in restoring the kingdom of Chu but eventually fell to the Han. Under the Later Han, control of the area returned to the settlement below Mount Kuaiji but authority over the Minyue hinterland was nominal at best and its Yue inhabitants largely retained their own political and social structures.
Is there an answer to this question: What wasn't the initial power base for Xiang Liang and Xiang Yu's rebellion?

Answer: unanswerable


Problem: The Blitz:

While Knickebein was used by German crews en masse, X-Gerät use was limited to specially trained pathfinder crews. Special receivers were mounted in He 111s, with a radio mast on the bomber's fuselage. The system worked on a higher frequency (66–77 MHz, compared to Knickebein's 30–33 MHz). Transmitters on the ground sent pulses at a rate of 180 per minute. X-Gerät received and analysed the pulses, giving the pilot both visual and aural "on course" signals. Three beams intersected the beam along the He 111's flight path. The first cross-beam acted as a warning for the bomb-aimer to start the bombing-clock which he would activate only when the second cross-beam was reached. When the third cross-beam was reached the bomb aimer activated a third trigger, which stopped the first hand of the equipment's clock, with the second hand continuing. When the second hand re-aligned with the first, the bombs were released. The clock's timing mechanism was co-ordinated with the distances of the intersecting beams from the target so the target was directly below when the bomb release occurred.

When the bomber crossed the first beam the bomber-aimer did what?
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A:
start the bombing-clock