Problem: Frederic Chopin:

Although the two displayed great respect and admiration for each other, their friendship was uneasy and had some qualities of a love-hate relationship. Harold C. Schonberg believes that Chopin displayed a "tinge of jealousy and spite" towards Liszt's virtuosity on the piano, and others have also argued that he had become enchanted with Liszt's theatricality, showmanship and success. Liszt was the dedicatee of Chopin's Op. 10 Etudes, and his performance of them prompted the composer to write to Hiller, "I should like to rob him of the way he plays my studies." However, Chopin expressed annoyance in 1843 when Liszt performed one of his nocturnes with the addition of numerous intricate embellishments, at which Chopin remarked that he should play the music as written or not play it at all, forcing an apology. Most biographers of Chopin state that after this the two had little to do with each other, although in his letters dated as late as 1848 he still referred to him as "my friend Liszt". Some commentators point to events in the two men's romantic lives which led to a rift between them; there are claims that Liszt had displayed jealousy of his mistress Marie d'Agoult's obsession with Chopin, while others believe that Chopin had become concerned about Liszt's growing relationship with George Sand.

Who did Chopin dedicate the Op. 10 Etudes to?
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A: Liszt

Problem: The basic ingredients of beer are water; a starch source, such as malted barley, able to be saccharified (converted to sugars) then fermented (converted into ethanol and carbon dioxide); a brewer's yeast to produce the fermentation; and a flavouring such as hops. A mixture of starch sources may be used, with a secondary starch source, such as maize (corn), rice or sugar, often being termed an adjunct, especially when used as a lower-cost substitute for malted barley. Less widely used starch sources include millet, sorghum and cassava root in Africa, and potato in Brazil, and agave in Mexico, among others. The amount of each starch source in a beer recipe is collectively called the grain bill.
What are several widely used starch sources that are used and found in various countries?
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Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Rothko also began using the new synthetic pigments, but not always with happy results. In 1962 he donated to Harvard University a series of large murals of the Passion of Christ whose predominant colors were dark pink and deep crimson. He mixed mostly traditional colors to make the pink and crimson; synthetic ultramarine, cerulean blue, and titanium white, but he also used two new organic reds, Naphtol and Lithol. The Naphtol did well, but the Lithol slowly changed color when exposed to light. Within five years the deep pinks and reds had begun to turn light blue, and by 1979 the paintings were ruined and had to be taken down.
What year were synthetic pigments first used?
A: unanswerable

Context and question: Antarctica is colder than the Arctic for three reasons. First, much of the continent is more than 3,000 m (9,800 ft) above sea level, and temperature decreases with elevation in the troposphere. Second, the Arctic Ocean covers the north polar zone: the ocean's relative warmth is transferred through the icepack and prevents temperatures in the Arctic regions from reaching the extremes typical of the land surface of Antarctica. Third, the Earth is at aphelion in July (i.e., the Earth is farthest from the Sun in the Antarctic winter), and the Earth is at perihelion in January (i.e., the Earth is closest to the Sun in the Antarctic summer). The orbital distance contributes to a colder Antarctic winter (and a warmer Antarctic summer) but the first two effects have more impact.
How many reasons are given for the Arctic being colder than Antarctica?
Answer: unanswerable

Question: With successive Persian rule, the region, divided between Syria-Coele province and later the autonomous Yehud Medinata, was gradually developing back into urban society, largely dominated by Judeans. The Greek conquests largely skipped the region without any resistance or interest. Incorporated into Ptolemaic and finally Seleucid Empires, the southern Levant was heavily hellenized, building the tensions between Judeans and Greeks. The conflict erupted in 167 BCE with the Maccabean Revolt, which succeeded in establishing an independent Hasmonean Kingdom in Judah, which later expanded over much of modern Israel, as the Seleucids gradually lost control in the region.
Is there an answer to this question: When did the conflict between Judeans and Greeks erupt?

Answer: 167 BCE

Problem: Pharmaceutical industry:

Depending on a number of considerations, a company may apply for and be granted a patent for the drug, or the process of producing the drug, granting exclusivity rights typically for about 20 years. However, only after rigorous study and testing, which takes 10 to 15 years on average, will governmental authorities grant permission for the company to market and sell the drug. Patent protection enables the owner of the patent to recover the costs of research and development through high profit margins for the branded drug. When the patent protection for the drug expires, a generic drug is usually developed and sold by a competing company. The development and approval of generics is less expensive, allowing them to be sold at a lower price. Often the owner of the branded drug will introduce a generic version before the patent expires in order to get a head start in the generic market. Restructuring has therefore become routine, driven by the patent expiration of products launched during the industry's "golden era" in the 1990s and companies' failure to develop sufficient new blockbuster products to replace lost revenues.

Governments grant permission to market drugs after how many years?
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A:
10 to 15 years on average