Problem: Geography of the United States:

The Great Plains lie west of the Mississippi River and east of the Rocky Mountains. A large portion of the country's agricultural products are grown in the Great Plains. Before their general conversion to farmland, the Great Plains were noted for their extensive grasslands, from tallgrass prairie in the eastern plains to shortgrass steppe in the western High Plains. Elevation rises gradually from less than a few hundred feet near the Mississippi River to more than a mile high in the High Plains. The generally low relief of the plains is broken in several places, most notably in the Ozark and Ouachita Mountains, which form the U.S. Interior Highlands, the only major mountainous region between the Rocky Mountains and the Appalachian Mountains.

Before being converted to grassland the Great Plains were known for what?
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A: unanswerable

Problem: Richard Phillips Feynman (/fanmn/; May 11, 1918 February 15, 1988) was an American theoretical physicist known for his work in the path integral formulation of quantum mechanics, the theory of quantum electrodynamics, and the physics of the superfluidity of supercooled liquid helium, as well as in particle physics for which he proposed the parton model. For his contributions to the development of quantum electrodynamics, Feynman, jointly with Julian Schwinger and Sin-Itiro Tomonaga, received the Nobel Prize in Physics in 1965. He developed a widely used pictorial representation scheme for the mathematical expressions governing the behavior of subatomic particles, which later became known as Feynman diagrams. During his lifetime, Feynman became one of the best-known scientists in the world. In a 1999 poll of 130 leading physicists worldwide by the British journal Physics World he was ranked as one of the ten greatest physicists of all time.
In what year did Feynman win his Nobel Prize?
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Answer: 1965

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
New Haven's greatest culinary claim to fame may be its pizza, which has been claimed to be among the best in the country, or even in the world. New Haven-style pizza, called "apizza" (pronounced ah-BEETS, [apitts] in the original Italian dialect), made its debut at the iconic Frank Pepe Pizzeria Napoletana (known as Pepe's) in 1925. Apizza is baked in coal- or wood-fired brick ovens, and is notable for its thin crust. Apizza may be red (with a tomato-based sauce) or white (with a sauce of garlic and olive oil), and pies ordered "plain" are made without the otherwise customary mozzarella cheese (originally smoked mozzarella, known as "scamorza" in Italian). A white clam pie is a well-known specialty of the restaurants on Wooster Street in the Little Italy section of New Haven, including Pepe's and Sally's Apizza (which opened in 1938). Modern Apizza on State Street, which opened in 1934, is also well-known.
White clam pie is found in what district of New Haven?
A: Wooster Street in the Little Italy section

Context and question: The city is home to 15 am and FM radio stations, two of which are French-language stations. St. John's is the only Canadian city served by radio stations whose call letters do not all begin with the letter C. The ITU prefix VO was assigned to the Dominion of Newfoundland before the province joined Canadian Confederation in 1949, and three AM stations kept their existing call letters. However, other commercial radio stations in St. John's which went to air after 1949 use the same range of prefixes (CFCK) currently in use elsewhere in Canada, with the exception of VOCM-FM, which was permitted to adopt the VOCM callsign because of its corporate association with the AM station that already bore that callsign. VO also remains in use in amateur radio.
How many French-language stations does the city have?
Answer: two

Question: As the summit closed on 28 September 1970, hours after escorting the last Arab leader to leave, Nasser suffered a heart attack. He was immediately transported to his house, where his physicians tended to him. Nasser died several hours later, around 6:00 p.m. Heikal, Sadat, and Nasser's wife Tahia were at his deathbed. According to his doctor, al-Sawi Habibi, Nasser's likely cause of death was arteriosclerosis, varicose veins, and complications from long-standing diabetes. Nasser was a heavy smoker with a family history of heart diseasetwo of his brothers died in their fifties from the same condition. The state of Nasser's health was not known to the public prior to his death. He had previously suffered heart attacks in 1966 and September 1969.
Is there an answer to this question: How old were Nasser's brothers when they died?

Answer: in their fifties

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The word "dollar" is one of the words in the first paragraph of Section 9 of Article 1 of the U.S. Constitution. In that context, "dollars" is a reference to the Spanish milled dollar, a coin that had a monetary value of 8 Spanish units of currency, or reales. In 1792 the U.S. Congress adopted legislation titled An act establishing a mint, and regulating the Coins of the United States. Section 9 of that act authorized the production of various coins, including "DOLLARS OR UNITSeach to be of the value of a Spanish milled dollar as the same is now current, and to contain three hundred and seventy-one grains and four sixteenth parts of a grain of pure, or four hundred and sixteen grains of standard silver". Section 20 of the act provided, "That the money of account of the United States shall be expressed in dollars, or units... and that all accounts in the public offices and all proceedings in the courts of the United States shall be kept and had in conformity to this regulation". In other words, this act designated the United States dollar as the unit of currency of the United States.
What is "dollars" a reference to?
A:
the Spanish milled dollar