Problem: United States dollar:

Early releases of the Washington coin included error coins shipped primarily from the Philadelphia mint to Florida and Tennessee banks. Highly sought after by collectors, and trading for as much as $850 each within a week of discovery, the error coins were identified by the absence of the edge impressions "E PLURIBUS UNUM IN GOD WE TRUST 2007 P". The mint of origin is generally accepted to be mostly Philadelphia, although identifying the source mint is impossible without opening a mint pack also containing marked units. Edge lettering is minted in both orientations with respect to "heads", some amateur collectors were initially duped into buying "upside down lettering error" coins. Some cynics also erroneously point out that the Federal Reserve makes more profit from dollar bills than dollar coins because they wear out in a few years, whereas coins are more permanent. The fallacy of this argument arises because new notes printed to replace worn out notes, which have been withdrawn from circulation, bring in no net revenue to the government to offset the costs of printing new notes and destroying the old ones. As most vending machines are incapable of making change in banknotes, they commonly accept only $1 bills, though a few will give change in dollar coins.

What do vending machines commonly only accept?
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A: $1 bills

Problem: Although professional wrestling in Mexico (lucha libre) also has stories and characters, they are less emphasized. Wrestlers in Mexico are traditionally more agile and perform more aerial maneuvers than professional wrestlers in the U.S. who, more often, rely on power moves and strikes to subdue their opponents. The difference in styles is due to the independent evolution of the sport in Mexico beginning in the 1930s and the fact that wrestlers in the cruiserweight division (peso semicompleto) are often the most popular wrestlers in Mexican lucha libre. Wrestlers often execute high flying moves characteristic of lucha libre by utilizing the wrestling ring's ropes to catapult themselves towards their opponents, using intricate combinations in rapid-fire succession, and applying complex submission holds. Lucha libre is also known for its tag team wrestling matches, in which the teams are often made up of three members, instead of two as is common in the U.S.
How do characters differ in Mexican wrestling?
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Answer: they are less emphasized

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The Yoga school builds on the Samkhya school theory that jnana (knowledge) is a sufficient means to moksha. It suggests that systematic techniques/practice (personal experimentation) combined with Samkhya's approach to knowledge is the path to moksha. Yoga shares several central ideas with Advaita Vedanta, with the difference that Yoga is a form of experimental mysticism while Advaita Vedanta is a form of monistic personalism. Like Advaita Vedanta, the Yoga school of Hindu philosophy states that liberation/freedom in this life is achievable, and this occurs when an individual fully understands and realizes the equivalence of Atman (soul, self) and Brahman.
What is the meaning of jnana?
A: knowledge

Context and question: A new approach to avoiding overhead wires is taken by the "second generation" tram/streetcar system in Bordeaux, France (entry into service of the first line in December 2003; original system discontinued in 1958) with its APS (alimentation par sol ground current feed). This involves a third rail which is flush with the surface like the tops of the running rails. The circuit is divided into segments with each segment energized in turn by sensors from the car as it passes over it, the remainder of the third rail remaining "dead". Since each energized segment is completely covered by the lengthy articulated cars, and goes dead before being "uncovered" by the passage of the vehicle, there is no danger to pedestrians. This system has also been adopted in some sections of the new tram systems in Reims, France (opened 2011) and Angers, France (also opened 2011). Proposals are in place for a number of other new services including Dubai, UAE; Barcelona, Spain; Florence, Italy; Marseille, France; Gold Coast, Australia; Washington, D.C., U.S.A.; Brasilia, Brazil and Tours, France.
An old approach to avoiding overhead wires is taken by what system?
Answer: unanswerable

Question: Following his ascension to power, Gaddafi moved into the Bab al-Azizia barracks, a six-mile long fortified compound located two miles from the center of Tripoli. His home and office at Azizia was a bunker designed by West German engineers, while the rest of his family lived in a large two-story building. Within the compound were also two tennis courts, a soccer field, several gardens, camels, and a Bedouin tent in which he entertained guests. In the 1980s, his lifestyle was considered modest in comparison to those of many other Arab leaders. Gaddafi allegedly worked for years with Swiss banks to launder international banking transactions. In November 2011, The Sunday Times identified property worth 1 billion in the UK that Gaddafi allegedly owned. Gaddafi had an Airbus A340 private jet, which he bought from Prince Al-Waleed bin Talal of Saudi Arabia for $120 million in 2003. Operated by Tripoli-based Afriqiyah Airways and decorated externally in their colours, it had various luxuries including a jacuzzi.
Is there an answer to this question: What was the value of Gaddafi's supposed British property holdings as of November 2011?

Answer: 1 billion

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Elevators with more than 30 m (98 ft) of travel have a system called compensation. This is a separate set of cables or a chain attached to the bottom of the counterweight and the bottom of the elevator cab. This makes it easier to control the elevator, as it compensates for the differing weight of cable between the hoist and the cab. If the elevator cab is at the top of the hoist-way, there is a short length of hoist cable above the car and a long length of compensating cable below the car and vice versa for the counterweight. If the compensation system uses cables, there will be an additional sheave in the pit below the elevator, to guide the cables. If the compensation system uses chains, the chain is guided by a bar mounted between the counterweight railway lines.
"Compensation" is the name of the system used for what type of elevators?
A:
Elevators with more than 30 m (98 ft) of travel