Problem: Frederic Chopin:

In 1841, Leon Escudier wrote of a recital given by Chopin that year, "One may say that Chopin is the creator of a school of piano and a school of composition. In truth, nothing equals the lightness, the sweetness with which the composer preludes on the piano; moreover nothing may be compared to his works full of originality, distinction and grace." Chopin refused to conform to a standard method of playing and believed that there was no set technique for playing well. His style was based extensively on his use of very independent finger technique. In his Projet de methode he wrote: "Everything is a matter of knowing good fingering ... we need no less to use the rest of the hand, the wrist, the forearm and the upper arm." He further stated: "One needs only to study a certain position of the hand in relation to the keys to obtain with ease the most beautiful quality of sound, to know how to play short notes and long notes, and [to attain] unlimited dexterity." The consequences of this approach to technique in Chopin's music include the frequent use of the entire range of the keyboard, passages in double octaves and other chord groupings, swiftly repeated notes, the use of grace notes, and the use of contrasting rhythms (four against three, for example) between the hands.

What writing of Chopin talks about everything about piano playing has to do with proper fingering?
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A: his Projet de methode

Problem: Thomas J. Watson, Sr., fired from the National Cash Register Company by John Henry Patterson, called on Flint and, in 1914, was offered CTR. Watson joined CTR as General Manager then, 11 months later, was made President when court cases relating to his time at NCR were resolved. Having learned Patterson's pioneering business practices, Watson proceeded to put the stamp of NCR onto CTR's companies. He implemented sales conventions, "generous sales incentives, a focus on customer service, an insistence on well-groomed, dark-suited salesmen and had an evangelical fervor for instilling company pride and loyalty in every worker". His favorite slogan, "THINK", became a mantra for each company's employees. During Watson's first four years, revenues more than doubled to $9 million and the company's operations expanded to Europe, South America, Asia and Australia. "Watson had never liked the clumsy hyphenated title of the CTR" and chose to replace it with the more expansive title "International Business Machines". First as a name for a 1917 Canadian subsidiary, then as a line in advertisements. For example, the McClures magazine, v53, May 1921, has a full page ad with, at the bottom:
The revenues did what under the first 4 years of Watson being president?
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Answer: more than doubled to $9 million

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Green is common in nature, as many plants are green because of a complex chemical known as chlorophyll, which is involved in photosynthesis. Chlorophyll absorbs the long wavelengths of light (red) and short wavelengths of light (blue) much more efficiently than the wavelengths that appear green to the human eye, so light reflected by plants is enriched in green. Chlorophyll absorbs green light poorly because it first arose in organisms living in oceans where purple halobacteria were already exploiting photosynthesis. Their purple color arose because they extracted energy in the green portion of the spectrum using bacteriorhodopsin. The new organisms that then later came to dominate the extraction of light were selected to exploit those portions of the spectrum not used by the halobacteria.
Why are many plants green?
A: chlorophyll

Context and question: Tuvalu experiences the effects of El Nino and La Nina caused by changes in ocean temperatures in the equatorial and central Pacific. El Nino effects increase the chances of tropical storms and cyclones, while La Nina effects increase the chances of drought. Typically the islands of Tuvalu receive between 200 to 400 mm (8 to 16 in) of rainfall per month. However, in 2011 a weak La Nina effect caused a drought by cooling the surface of the sea around Tuvalu. A state of emergency was declared on 28 September 2011; with rationing of fresh-water on the islands of Funafuti and Nukulaelae. Households on Funafuti and Nukulaelae were restricted to two buckets of fresh water per day (40 litres).
What did a drought in 2011 cause on Funafuti?
Answer: rationing of fresh-water

Question: The 150th anniversary of Bell's birth in 1997 was marked by a special issue of commemorative 1 banknotes from the Royal Bank of Scotland. The illustrations on the reverse of the note include Bell's face in profile, his signature, and objects from Bell's life and career: users of the telephone over the ages; an audio wave signal; a diagram of a telephone receiver; geometric shapes from engineering structures; representations of sign language and the phonetic alphabet; the geese which helped him to understand flight; and the sheep which he studied to understand genetics. Additionally, the Government of Canada honored Bell in 1997 with a C$100 gold coin, in tribute also to the 150th anniversary of his birth, and with a silver dollar coin in 2009 in honor of the 100th anniversary of flight in Canada. That first flight was made by an airplane designed under Dr. Bell's tutelage, named the Silver Dart. Bell's image, and also those of his many inventions have graced paper money, coinage and postal stamps in numerous countries worldwide for many dozens of years.
Is there an answer to this question: What form of currency did Canada issue to celebrate Bell in 1997?

Answer: C$100 gold coin

Problem: The Blitz:

In general, German bombers were likely to get through to their targets without too much difficulty. It was to be some months before an effective night fighter force would be ready, and anti-aircraft defences only became adequate after the Blitz was over, so ruses were created to lure German bombers away from their targets. Throughout 1940, dummy airfields were prepared, good enough to stand up to skilled observation. A number[clarification needed] of bombs fell on these diversionary ("Starfish") targets.

What kind of airfields were prepared to stand up to skilled observers?
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A:
dummy