Problem: United States dollar:

Under the Bretton Woods system established after World War II, the value of gold was fixed to $35 per ounce, and the value of the U.S. dollar was thus anchored to the value of gold. Rising government spending in the 1960s, however, led to doubts about the ability of the United States to maintain this convertibility, gold stocks dwindled as banks and international investors began to convert dollars to gold, and as a result the value of the dollar began to decline. Facing an emerging currency crisis and the imminent danger that the United States would no longer be able to redeem dollars for gold, gold convertibility was finally terminated in 1971 by President Nixon, resulting in the "Nixon shock".

What was the value of the Nixon investors linked to?
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A: unanswerable

Problem: Materialism developed, possibly independently, in several geographically separated regions of Eurasia during what Karl Jaspers termed the Axial Age (approximately 800 to 200 BC).
In what part of the world did materialism develop during the non-Axial Age?
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Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
HDTV technology was introduced in the United States in the late 1980s and made official in 1993 by the Digital HDTV Grand Alliance, a group of television, electronic equipment, communications companies consisting of AT&T Bell Labs, General Instrument, Philips, Sarnoff, Thomson, Zenith and the Massachusetts Institute of Technology. Field testing of HDTV at 199 sites in the United States was completed August 14, 1994. The first public HDTV broadcast in the United States occurred on July 23, 1996 when the Raleigh, North Carolina television station WRAL-HD began broadcasting from the existing tower of WRAL-TV southeast of Raleigh, winning a race to be first with the HD Model Station in Washington, D.C., which began broadcasting July 31, 1996 with the callsign WHD-TV, based out of the facilities of NBC owned and operated station WRC-TV. The American Advanced Television Systems Committee (ATSC) HDTV system had its public launch on October 29, 1998, during the live coverage of astronaut John Glenn's return mission to space on board the Space Shuttle Discovery. The signal was transmitted coast-to-coast, and was seen by the public in science centers, and other public theaters specially equipped to receive and display the broadcast.
When did the last public HDTV broadcast happen in the US?
A: unanswerable

Context and question: The main campus in Provo, Utah, United States sits on approximately 560 acres (2.3 km2) nestled at the base of the Wasatch Mountains and includes 295 buildings. The buildings feature a wide variety of architectural styles, each building being built in the style of its time. The grass, trees, and flower beds on BYU's campus are impeccably maintained. Furthermore, views of the Wasatch Mountains, (including Mount Timpanogos) can be seen from the campus. BYU's Harold B. Lee Library (also known as "HBLL"), which The Princeton Review ranked as the No. 1 "Great College Library" in 2004, has approximately 8 million items in its collections, contains 98 miles (158 km) of shelving, and can seat 4,600 people. The Spencer W. Kimball Tower, shortened to SWKT and pronounced Swicket by many students, is home to several of the university's departments and programs and is the tallest building in Provo, Utah. Furthermore, BYU's Marriott Center, used as a basketball arena, can seat over 22,000 and is one of the largest on-campus arenas in the nation. Interestingly absent on the campus of this church owned university is a campus chapel. Notwithstanding, each Sunday LDS Church services for students are conducted on campus, but due to the large number of students attending these services, nearly all of the buildings and possible meeting spaces on campus are utilized (in addition, many students attend services off campus in LDS chapels in the surrounding communities).
What sits on 295 acres in Provo, Utah?
Answer: unanswerable

Question: During the years 1940-1955, the rate of decline in the U.S. death rate accelerated from 2% per year to 8% per year, then returned to the historical rate of 2% per year. The dramatic decline in the immediate post-war years has been attributed to the rapid development of new treatments and vaccines for infectious disease that occurred during these years. Vaccine development continued to accelerate, with the most notable achievement of the period being Jonas Salk's 1954 development of the polio vaccine under the funding of the non-profit National Foundation for Infantile Paralysis. The vaccine process was never patented, but was instead given to pharmaceutical companies to manufacture as a low-cost generic. In 1960 Maurice Hilleman of Merck Sharp & Dohme identified the SV40 virus, which was later shown to cause tumors in many mammalian species. It was later determined that SV40 was present as a contaminant in polio vaccine lots that had been administered to 90% of the children in the United States. The contamination appears to have originated both in the original cell stock and in monkey tissue used for production. In 2004 the United States Cancer Institute announced that it had concluded that SV40 is not associated with cancer in people.
Is there an answer to this question: What was a complication of the SV50 virus?

Answer: unanswerable

QUES: Clinton returned in 1780 with 14,000 soldiers. American General Benjamin Lincoln was trapped and surrendered his entire 5,400-man force after a long fight, and the Siege of Charles Towne was the greatest American defeat of the war. Several Americans who escaped the carnage joined other militias, including those of Francis Marion, the "Swamp Fox"; and Andrew Pickens. The British retained control of the city until December 1782. After the British left, the city's name was officially changed to Charleston in 1783.

How many soldiers didn't General Lincoln lead?
What is the answer?
ANS:
unanswerable