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In the late 1960s, the term heavy metal was used interchangeably with hard rock, but gradually began to be used to describe music played with even more volume and intensity. While hard rock maintained a bluesy rock and roll identity, including some swing in the back beat and riffs that tended to outline chord progressions in their hooks, heavy metal's riffs often functioned as stand-alone melodies and had no swing in them. Heavy metal took on "darker" characteristics after Black Sabbath's breakthrough at the beginning of the 1970s. In the 1980s it developed a number of subgenres, often termed extreme metal, some of which were influenced by hardcore punk, and which further differentiated the two styles. Despite this differentiation, hard rock and heavy metal have existed side by side, with bands frequently standing on the boundary of, or crossing between, the genres.
What genre was an influence on extreme metal in the 1980s?
A: hardcore punk

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1 CATOBAR carrier: Charles de Gaulle is a 42,000 tonne nuclear-powered aircraft carrier, commissioned in 2001 and is the flagship of the French Navy (Marine Nationale). The ship carries a complement of Dassault-Breguet Super Etendard, Dassault Rafale M and E2C Hawkeye aircraft, EC725 Caracal and AS532 Cougar helicopters for combat search and rescue, as well as modern electronics and Aster missiles. It is a CATOBAR-type carrier that uses two 75 m C133 steam catapults of a shorter version of the catapult system installed on the U.S. Nimitz-class carriers, one catapult at the bow and one across the front of the landing area.
What type of missiles does the Charles de Gaulle carry?
A: Aster

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England is quite a successful nation at the UEFA European Football Championship, having finished in third place in 1968 and reached the semi-final in 1996. England hosted Euro 96 and have appeared in eight UEFA European Championship Finals tournaments, tied for ninth-best. The team has also reached the quarter-final on two recent occasions in 2004 and 2012. The team's worst result in the competition was a first-round elimination in 1980, 1988, 1992 and 2000. The team did not enter in 1960, and they failed to qualify in 1964, 1972, 1976, 1984, and 2008.
In what country was the 1980 UEFA European Football Championship held?
A: unanswerable

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Incubation, which optimises temperature for chick development, usually begins after the last egg has been laid. In monogamous species incubation duties are often shared, whereas in polygamous species one parent is wholly responsible for incubation. Warmth from parents passes to the eggs through brood patches, areas of bare skin on the abdomen or breast of the incubating birds. Incubation can be an energetically demanding process; adult albatrosses, for instance, lose as much as 83 grams (2.9 oz) of body weight per day of incubation. The warmth for the incubation of the eggs of megapodes comes from the sun, decaying vegetation or volcanic sources. Incubation periods range from 10 days (in woodpeckers, cuckoos and passerine birds) to over 80 days (in albatrosses and kiwis).
When does incubation begin?
A:
after the last egg has been laid