Problem: Crimean War:

In the west, the Russians were dissuaded from attacking Vidin by the presence of the Austrian forces, which had swelled to 280,000 men. On 28 May 1854 a protocol of the Vienna Conference was signed by Austria and Russia. One of the aims of the Russian advance had been to encourage the Orthodox Christian Serbs and Bulgarians living under Ottoman rule to rebel. However, when the Russian troops actually crossed the River Pruth into Moldavia, the Orthodox Christians still showed no interest in rising up against the Turks.:131, 137 Adding to the worries of Nicholas I was the concern that Austria would enter the war against the Russians and attack his armies on the western flank. Indeed, after attempting to mediate a peaceful settlement between Russia and Turkey, the Austrians entered the war on the side of Turkey with an attack against the Russians in the Principalities which threatened to cut off the Russian supply lines. Accordingly, the Russians were forced to raise the siege of Silistra on 23 June 1854, and begin abandoning the Principalities.:185 The lifting of the siege reduced the threat of a Russian advance into Bulgaria.

Who didn't show any signs of rising up against the Turks?
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A: Orthodox Christians


Problem: European art music is largely distinguished from many other non-European and popular musical forms by its system of staff notation, in use since about the 16th century. Western staff notation is used by composers to prescribe to the performer the pitches (e.g., melodies, basslines and/or chords), tempo, meter and rhythms for a piece of music. This leaves less room for practices such as improvisation and ad libitum ornamentation, which are frequently heard in non-European art music and in popular music  styles such as jazz and blues. Another difference is that whereas most popular styles lend themselves to the song form, classical music has been noted for its development of highly sophisticated forms of instrumental music such as the concerto, symphony, sonata, and mixed vocal and instrumental styles such as opera which, since they are written down, can attain a high level of complexity.
What method is used by composers to prescribe to the performer the pitches, tempo, meter and rhythms for a piece of music?
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Answer: Western staff notation


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Vaccines rely on immune modulation or augmentation. Vaccination either excites or reinforces the immune competence of a host to ward off infection, leading to the activation of macrophages, the production of antibodies, inflammation, and other classic immune reactions. Antibacterial vaccines have been responsible for a drastic reduction in global bacterial diseases. Vaccines made from attenuated whole cells or lysates have been replaced largely by less reactogenic, cell-free vaccines consisting of purified components, including capsular polysaccharides and their conjugates, to protein carriers, as well as inactivated toxins (toxoids) and proteins.
What do polysaccharides need to work?
A: unanswerable


Context and question: Northwestern is a large, residential research university. Accredited by the North Central Association of Colleges and Schools and the respective national professional organizations for chemistry, psychology, business, education, journalism, music, engineering, law, and medicine, the university offers 124 undergraduate programs and 145 graduate and professional programs. Northwestern conferred 2,190 bachelor's degrees, 3,272 master's degrees, 565 doctoral degrees, and 444 professional degrees in 2012–2013.
 How many bachelor's degrees did Southwestern confer during the 2012-2013 school term?
Answer: unanswerable


Question: England qualified for the 1970 FIFA World Cup in Mexico as reigning champions, and reached the quarter-finals, where they were knocked out by West Germany. England had been 2–0 up, but were eventually beaten 3–2 after extra time. They failed in qualification for the 1974, leading to Ramsey's dismissal, and 1978 FIFA World Cups. Under Ron Greenwood, they managed to qualify for the 1982 FIFA World Cup in Spain (the first time competitively since 1962); despite not losing a game, they were eliminated in the second group stage.
Is there an answer to this question: In what year did Ron Greenwood take over leadership of England's football team?

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.

What mechanism cause the bombs to be released?
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A:
clock's timing