This task is about creating an unanswerable question based on a given passage. Construct a question that looks relevant to the given context but is unanswerable. Following are a few suggestions about how to create unanswerable questions:
(i) create questions which require satisfying a constraint that is not mentioned in the passage
(ii) create questions which require information beyond what is provided in the passage in order to answer
(iii) replace an existing entity, number, date mentioned in the passage with other entity, number, date and use it in the question
(iv) create a question which is answerable from the passage and then replace one or two words by their antonyms or insert/remove negation words to make it unanswerable.

Q: Passage: 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.

A: What is specifically produced for budget constraints?
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Q: Passage: The average Mongol garrison family of the Yuan dynasty seems to have lived a life of decaying rural leisure, with income from the harvests of their Chinese tenants eaten up by costs of equipping and dispatching men for their tours of duty. The Mongols practiced debt slavery, and by 1290 in all parts of the Mongol Empire commoners were selling their children into slavery. Seeing this as damaging to the Mongol nation, Kublai in 1291 forbade the sale abroad of Mongols. Kublai wished to persuade the Chinese that he was becoming increasingly sinicized while maintaining his Mongolian credentials with his own people. He set up a civilian administration to rule, built a capital within China, supported Chinese religions and culture, and devised suitable economic and political institutions for the court. But at the same time he never abandoned his Mongolian heritage.

A: By what year was selling children into slavery uncommon among the Mongols?
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Q: Passage: Zhejiang was part of the Wu during the Three Kingdoms. Wu (229280), commonly known as Eastern Wu or Sun Wu, had been the economically most developed state among the Three Kingdoms (220280 CE). The historical novel Romance of the Three Kingdoms records that Zhejiang had the best-equipped, strong navy force. The story depicts how the states of Wei () and Shu (), lack of material resources, avoided direct confrontation with the Wu. In armed military conflicts with Wu, the two states relied intensively on tactics of camouflage and deception to steal Wu's military resources including arrows and bows.

A:
When was Zhejiang part of the Lu?
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