Problem: Neptune:

Neptune is not visible to the unaided eye and is the only planet in the Solar System found by mathematical prediction rather than by empirical observation. Unexpected changes in the orbit of Uranus led Alexis Bouvard to deduce that its orbit was subject to gravitational perturbation by an unknown planet. Neptune was subsequently observed with a telescope on 23 September 1846 by Johann Galle within a degree of the position predicted by Urbain Le Verrier. Its largest moon, Triton, was discovered shortly thereafter, though none of the planet's remaining known 14 moons were located telescopically until the 20th century. The planet's distance from Earth gives it a very small apparent size, making it challenging to study with Earth-based telescopes. Neptune was visited by Voyager 2, when it flew by the planet on 25 August 1989. The advent of Hubble Space Telescope and large ground-based telescopes with adaptive optics has recently allowed for additional detailed observations from afar.

What is the only planet in the solar system found by empirical observation?
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A: unanswerable

Problem: In 2008, Bloomberg claimed child labour in copper and cobalt mines that supplied Chinese companies in Congo. The children are creuseurs, that is they dig the ore by hand, carry sacks of ores on their backs, and these are then purchased by these companies. Over 60 of Katanga's 75 processing plants are owned by Chinese companies and 90 percent of the region's minerals go to China. An African NGO report claimed 80,000 child labourers under the age of 15, or about 40% of all miners, were supplying ore to Chinese companies in this African region. Amnesty International alleged in 2016 that some cobalt sold by Congo Dongfang Mining was produced by child labor, and that it was being used in lithium-ion batteries powering electric cars and mobile devices worldwide.
What is the cobalt used for?
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Answer: lithium-ion batteries powering electric cars and mobile devices worldwide

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The Nazi regime under Adolf Hitler came to power in 1933, and along with Mussolini's Italy sought to gain control of the continent by the Second World War. Following the Allied victory in the Second World War, Europe was divided by the Iron Curtain. The countries in Southeastern Europe were dominated by the Soviet Union and became communist states. The major non-communist Southern European countries joined a US-led military alliance (NATO) and formed the European Economic Community amongst themselves. The countries in the Soviet sphere of influence joined the military alliance known as the Warsaw Pact and the economic bloc called Comecon. Yugoslavia was neutal.
What divided the Nazi regime?
A: unanswerable

Context and question: All versions of the SNES are predominantly gray, although the exact shade may differ. The original North American version, designed by Nintendo of America industrial designer Lance Barr (who previously redesigned the Famicom to become the NES), has a boxy design with purple sliding switches and a dark gray eject lever. The loading bay surface is curved, both to invite interaction and to prevent food or drinks from being placed on the console and spilling as had happened with the flat surfaced NES. The Japanese and European versions are more rounded, with darker gray accents and buttons. The North American SNS-101 model and the Japanese Super Famicom Jr. (the SHVC-101 model), all designed by Barr, are both smaller with a rounded contour; however, the SNS-101 buttons are purple where the Super Famicom Jr. buttons are gray. The European and American versions of the SNES controllers have much longer cables compared to the Japanese Super Famicom controllers.
What color were the buttons for the SNS-100 version from Japan?
Answer: unanswerable

Question: Major League Baseball is especially well known for red teams. The Cincinnati Red Stockings are the oldest professional baseball team, dating back to 1869. The franchise soon relocated to Boston and is now the Atlanta Braves, but its name survives as the origin for both the Cincinnati Reds and Boston Red Sox. During the 1950s when red was strongly associated with communism, the modern Cincinnati team was known as the "Redlegs" and the term was used on baseball cards. After the red scare faded, the team was known as the "Reds" again. The Los Angeles Angels of Anaheim are also known for their color red, as are the St. Louis Cardinals, Arizona Diamondbacks, and the Philadelphia Phillies.
Is there an answer to this question: What dates back to 1896?

Answer: unanswerable

Question: The United States Mint produces Proof Sets specifically for collectors and speculators. Silver Proofs tend to be the standard designs but with the dime, quarter, and half dollar containing 90% silver. Starting in 1983 and ending in 1997, the Mint also produced proof sets containing the year's commemorative coins alongside the regular coins. Another type of proof set is the Presidential Dollar Proof Set where four special $1 coins are minted each year featuring a president. Because of budget constraints and increasing stockpiles of these relatively unpopular coins, the production of new Presidential dollar coins for circulation was suspended on December 13, 2011, by U.S. Treasury Secretary Timothy F. Geithner. Future minting of such coins will be made solely for collectors.
Is there an answer to this question: What is the percentage of silver in coins in the budget constraints?

Answer:
unanswerable