Problem: BBC Television:

On 1 September 1939, two days before Britain declared war on Germany, the station was taken off air with little warning; the government was concerned that the VHF transmissions would act as a beacon to enemy aircraft homing in on London. Also, many of the television service's technical staff and engineers would be needed for the war effort, in particular on the radar programme. The last programme transmitted was a Mickey Mouse cartoon, Mickey's Gala Premier (1933), which was followed by test transmissions; this account refuted the popular memory according to which broadcasting was suspended before the end of the cartoon.

What day did Britain declare war on Germany?
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A: unanswerable

Problem: Nowadays, France only recognizes French as an official language. Nevertheless, on 10 December 2007, the General Council of the Pyrenees-Orientales officially recognized Catalan as one of the languages of the department and seeks to further promote it in public life and education.
What language does the General Council want to promote?
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Answer: Catalan

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The city's total area is 468.9 square miles (1,214 km2). 164.1 sq mi (425 km2) of this is water and 304.8 sq mi (789 km2) is land. The highest point in the city is Todt Hill on Staten Island, which, at 409.8 feet (124.9 m) above sea level, is the highest point on the Eastern Seaboard south of Maine. The summit of the ridge is mostly covered in woodlands as part of the Staten Island Greenbelt.
In square miles, how much of the city's total area is land?
A: 304.8

Context and question: The Protoevangelium of James, an extra-canonical book, has been the source of many Orthodox beliefs on Mary. The account of Mary's life presented includes her consecration as a virgin at the temple at age three. The High Priest Zachariah blessed Mary and informed her that God had magnified her name among many generations. Zachariah placed Mary on the third step of the altar, whereby God gave her grace. While in the temple, Mary was miraculously fed by an angel, until she was twelve years old. At that point an angel told Zachariah to betroth Mary to a widower in Israel, who would be indicated. This story provides the theme of many hymns for the Feast of Presentation of Mary, and icons of the feast depict the story. The Orthodox believe that Mary was instrumental in the growth of Christianity during the life of Jesus, and after his Crucifixion, and Orthodox Theologian Sergei Bulgakov wrote: "The Virgin Mary is the center, invisible, but real, of the Apostolic Church."
Which priest officiated at Mary's consecration?
Answer: Zachariah

Question: Gymnasts sprint down a runway, which is a maximum of 25 meters in length, before hurdling onto a spring board. The gymnast is allowed to choose where they start on the runway. The body position is maintained while "punching" (blocking using only a shoulder movement) the vaulting platform. The gymnast then rotates to a standing position. In advanced gymnastics, multiple twists and somersaults may be added before landing. Successful vaults depend on the speed of the run, the length of the hurdle, the power the gymnast generates from the legs and shoulder girdle, the kinesthetic awareness in the air, and the speed of rotation in the case of more difficult and complex vaults.
Is there an answer to this question: What is the maximum length of a runway?

Answer: 25 meters

Delicate sounds and fine overtones were mostly lost, because it took a lot of sound energy to vibrate the recording horn diaphragm and cutting mechanism. There were acoustic limitations due to mechanical resonances in both the recording and playback system. Some pictures of acoustic recording sessions show horns wrapped with tape to help mute these resonances. Even an acoustic recording played back electrically on modern equipment sounds like it was recorded through a horn, notwithstanding a reduction in distortion because of the modern playback. Toward the end of the acoustic era, there were many fine examples of recordings made with horns.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): What was the quality of sound recordings made with horns at the end of the acoustic era?
Ah, so..
many fine examples