Problem: Frédéric Chopin:

Frédéric François Chopin (/ˈʃoʊpæn/; French pronunciation: ​[fʁe.de.ʁik fʁɑ̃.swa ʃɔ.pɛ̃]; 22 February or 1 March 1810 – 17 October 1849), born Fryderyk Franciszek Chopin,[n 1] was a Polish and French (by citizenship and birth of father) composer and a virtuoso pianist of the Romantic era, who wrote primarily for the solo piano. He gained and has maintained renown worldwide as one of the leading musicians of his era, whose "poetic genius was based on a professional technique that was without equal in his generation." Chopin was born in what was then the Duchy of Warsaw, and grew up in Warsaw, which after 1815 became part of Congress Poland. A child prodigy, he completed his musical education and composed his earlier works in Warsaw before leaving Poland at the age of 20, less than a month before the outbreak of the November 1830 Uprising.

What year did Chopin die?
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A: 1849


Problem: Airports may also contain premium and VIP services. The premium and VIP services may include express check-in and dedicated check-in counters. These services are usually reserved for First and Business class passengers, premium frequent flyers, and members of the airline's clubs. Premium services may sometimes be open to passengers who are members of a different airline's frequent flyer program. This can sometimes be part of a reciprocal deal, as when multiple airlines are part of the same alliance, or as a ploy to attract premium customers away from rival airlines.
What type of services are sometimes open to passengers who are members of a different airline's frequent flyer program?
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Answer: Premium services


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The Kerrytown Shops, Main Street Business District, the State Street Business District, and the South University Business District are commercial areas in downtown Ann Arbor. Three commercial areas south of downtown include the areas near I-94 and Ann Arbor-Saline Road, Briarwood Mall, and the South Industrial area. Other commercial areas include the Arborland/Washtenaw Avenue and Packard Road merchants on the east side, the Plymouth Road area in the northeast, and the Westgate/West Stadium areas on the west side. Downtown contains a mix of 19th- and early-20th-century structures and modern-style buildings, as well as a farmers' market in the Kerrytown district. The city's commercial districts are composed mostly of two- to four-story structures, although downtown and the area near Briarwood Mall contain a small number of high-rise buildings.
Which area in the city is composed mostly of two-to-three story buildings?
A: unanswerable


Context and question: Early MPEG Layer III encoders used what is now called Constant Bit Rate (CBR). The software was only able to use a uniform bitrate on all frames in an MP3 file. Later more sophisticated MP3 encoders were able to use the bit reservoir to target an average bit rate selecting the encoding rate for each frame based on the complexity of the sound in that portion of the recording.
What did more sophisticated MP3 encoders use to target an average bit rate?
Answer: bit reservoir


Question: The Football League was founded in 1888, 16 years after the first FA Cup competition. Since the creation of The Football League, Tottenham Hotspur is the only non-league "giant-killer" to win the Cup, taking the 1901 FA Cup with a victory over reigning league runners-up Sheffield United: although at that time, there were only two divisions and 36 clubs in the Football League, and Spurs were champions of the next lowest football tier - the Southern League and probably already good enough for the First Division (as was shown when they joined the Second Division in 1908 and immediately won promotion to the First.) Only two other actual non-League clubs have even reached the final since the founding of the League: Sheffield Wednesday in 1890 (champions of the Football Alliance, a rival league which was already effectively the Second Division, which it formally became in 1892 – Wednesday being let straight into the First Division), and Southampton in 1900 and 1902 (in which years they were also Southern League champions, proving the strength of that league: again, they were probably of equivalent standard to a First Division club at the time, but Southampton's form subsequently faded and they did not join the League till 1920 and the formation of the Third Division.)
Is there an answer to this question: Which club has never reached the final?

Answer: unanswerable


Problem: Botany:

The algae are a polyphyletic group and are placed in various divisions, some more closely related to plants than others. There are many differences between them in features such as cell wall composition, biochemistry, pigmentation, chloroplast structure and nutrient reserves. The algal division Charophyta, sister to the green algal division Chlorophyta, is considered to contain the ancestor of true plants. The Charophyte class Charophyceae and the land plant sub-kingdom Embryophyta together form the monophyletic group or clade Streptophytina.

Are all species of algae similar?
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A:
many differences