Problem: Nanjing:

Nanjing first became a state capital in 229 AD, when the state of Eastern Wu founded by Sun Quan during the Three Kingdoms period relocated its capital to Jianye (建業), the city extended on the basis of Jinling Yi in 211 AD. Although conquered by the Western Jin dynasty in 280, Nanjing and its neighbouring areas had been well cultivated and developed into one of the commercial, cultural and political centers of China during the rule of East Wu. This city would soon play a vital role in the following centuries.

When did Nanjing become a state capital?
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A: 229 AD


Problem: Victoria married her first cousin, Prince Albert of Saxe-Coburg and Gotha, in 1840. Their nine children married into royal and noble families across the continent, tying them together and earning her the sobriquet "the grandmother of Europe". After Albert's death in 1861, Victoria plunged into deep mourning and avoided public appearances. As a result of her seclusion, republicanism temporarily gained strength, but in the latter half of her reign her popularity recovered. Her Golden and Diamond Jubilees were times of public celebration.
What year didn't Prince Albert die?
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Answer: unanswerable


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
External evidence is evidence of each physical witness, its date, source, and relationship to other known witnesses. Critics will often prefer the readings supported by the oldest witnesses. Since errors tend to accumulate, older manuscripts should have fewer errors. Readings supported by a majority of witnesses are also usually preferred, since these are less likely to reflect accidents or individual biases. For the same reasons, the most geographically diverse witnesses are preferred. Some manuscripts show evidence that particular care was taken in their composition, for example, by including alternative readings in their margins, demonstrating that more than one prior copy (exemplar) was consulted in producing the current one. Other factors being equal, these are the best witnesses. The role of the textual critic is necessary when these basic criteria are in conflict. For instance, there will typically be fewer early copies, and a larger number of later copies. The textual critic will attempt to balance these criteria, to determine the original text.
What characteristic of a compilation of witnesses is the most beneficial to a textual critic?
A: geographically diverse


Context and question: Although Mali has enjoyed a reasonably good inter-ethnic relationships based on the long history of coexistence, some hereditary servitude and bondage relationship exist, as well as ethnic tension between settled Songhai and nomadic Tuaregs of the north. Due to a backlash against the northern population after independence, Mali is now in a situation where both groups complain about discrimination on the part of the other group. This conflict also plays a role in the continuing Northern Mali conflict where there is a tension between both Tuaregs and the Malian government, and the Tuaregs and radical Islamists who are trying to establish sharia law.
What group of people are trying to establish sharia law?
Answer: radical Islamists


Question: Columbia founded Epic Records in 1953. In 1956, Conkling left Columbia, he would help establish the National Academy of Recording Arts and Sciences before eventually becoming the first president of the newly launched Warner Bros. Records, and Goddard Lieberson began the first of two stints as head of the record company. In 1958, Columbia founded another label, Date Records, which initially issued rockabilly music.
Is there an answer to this question: Epic Records founded Columbia in what year?

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: Other than the Silver Proof set, what other type of Proof set exists?

Answer:
Presidential Dollar Proof Set