Problem: BeiDou Navigation Satellite System:

Compass-M1 transmits in 3 bands: E2, E5B, and E6. In each frequency band two coherent sub-signals have been detected with a phase shift of 90 degrees (in quadrature). These signal components are further referred to as "I" and "Q". The "I" components have shorter codes and are likely to be intended for the open service. The "Q" components have much longer codes, are more interference resistive, and are probably intended for the restricted service. IQ modulation has been the method in both wired and wireless digital modulation since morsetting carrier signal 100 years ago.

In how many bands does Nerf-M1 transmit in?
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A: unanswerable

Problem: Association football:

There has been a football tournament at every Summer Olympic Games since 1900, except at the 1932 games in Los Angeles. Before the inception of the World Cup, the Olympics (especially during the 1920s) had the same status as the World Cup. Originally, the event was for amateurs only; however, since the 1984 Summer Olympics, professional players have been permitted, albeit with certain restrictions which prevent countries from fielding their strongest sides. The Olympic men's tournament is played at Under-23 level. In the past the Olympics have allowed a restricted number of over-age players per team. A women's tournament was added in 1996; in contrast to the men's event, full international sides without age restrictions play the women's Olympic tournament.

What was the last year that there was a football tournament at the Winter Olympics?
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A: unanswerable

Problem: Neoclassical architecture:

At the forefront of the new school of design was the aristocratic "architect earl", Richard Boyle, 3rd Earl of Burlington; in 1729, he and William Kent, designed Chiswick House. This House was a reinterpretation of Palladio's Villa Capra, but purified of 16th century elements and ornament. This severe lack of ornamentation was to be a feature of the Palladianism. In 1734 William Kent and Lord Burlington designed one of England's finest examples of Palladian architecture with Holkham Hall in Norfolk. The main block of this house followed Palladio's dictates quite closely, but Palladio's low, often detached, wings of farm buildings were elevated in significance.

What was a reinterpretation of Richard Boyles Chiswick House?
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A: unanswerable

Problem: North Carolina:

The coastal plain transitions to the Piedmont region along the Atlantic Seaboard fall line, a line which marks the elevation at which waterfalls first appear on streams and rivers. The Piedmont region of central North Carolina is the state's most urbanized and densely populated section. It consists of gently rolling countryside frequently broken by hills or low mountain ridges. Small, isolated, and deeply eroded mountain ranges and peaks are located in the Piedmont, including the Sauratown Mountains, Pilot Mountain, the Uwharrie Mountains, Crowder's Mountain, King's Pinnacle, the Brushy Mountains, and the South Mountains. The Piedmont ranges from about 300 to 400 feet (91 to 122 m) in elevation in the east to over 1,000 feet (300 m) in the west. Because of the rapid population growth in the Piedmont, a significant part of the rural area in this region is being transformed into suburbs with shopping centers, housing, and corporate offices. Agriculture is steadily declining in importance. The major rivers of the Piedmont, such as the Yadkin and Catawba, tend to be fast-flowing, shallow, and narrow.

What do you call the line that marks the elevation that waterfalls first appear on rivers?
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A:
Atlantic Seaboard fall line