Problem: States of Germany:

The governments in Berlin, Bremen and Hamburg are designated by the term Senate. In the three free states of Bavaria, Saxony, and Thuringia the government is referred to as the State Government (Staatsregierung), and in the other ten states the term Land Government (Landesregierung) is used. Before January 1, 2000, Bavaria had a bicameral parliament, with a popularly elected Landtag, and a Senate made up of representatives of the state's major social and economic groups. The Senate was abolished following a referendum in 1998. The states of Berlin, Bremen, and Hamburg are governed slightly differently from the other states. In each of those cities, the executive branch consists of a Senate of approximately eight, selected by the state's parliament; the senators carry out duties equivalent to those of the ministers in the larger states. The equivalent of the Minister-President is the Senatsprasident (President of the Senate) in Bremen, the Erster Burgermeister (First Mayor) in Hamburg, and the Regierender Burgermeister (Governing Mayor) in Berlin. The parliament for Berlin is called the Abgeordnetenhaus (House of Representatives), while Bremen and Hamburg both have a Burgerschaft. The parliaments in the remaining 13 states are referred to as Landtag (State Parliament).

What are the governments in Berlin, Bremen and Hamburg called?
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A: Senate

Problem: Red:

Unlike vermilion or red ochre, made from minerals, red lake pigments are made by mixing organic dyes, made from insects or plants, with white chalk or alum. Red lac was made from the gum lac, the dark red resinous substance secreted by various scale insects, particularly the Laccifer lacca from India. Carmine lake was made from the cochineal insect from Central and South America, Kermes lake came from a different scale insect, kermes vermilio, which thrived on oak trees around the Mediterranean. Other red lakes were made from the rose madder plant and from the brazilwood tree.

What was red ochre composed of?
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A: minerals

Problem: Paper:

Paper made from wood pulp is not necessarily less durable than a rag paper. The ageing behavior of a paper is determined by its manufacture, not the original source of the fibres. Furthermore, tests sponsored by the Library of Congress prove that all paper is at risk of acid decay, because cellulose itself produces formic, acetic, lactic and oxalic acids.

What is definitely more durable than rag paper?
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A: unanswerable

Problem: Hard rock:

In the early 1970s the Rolling Stones developed their hard rock sound with Exile on Main St. (1972). Initially receiving mixed reviews, according to critic Steve Erlewine it is now "generally regarded as the Rolling Stones' finest album". They continued to pursue the riff-heavy sound on albums including It's Only Rock 'n' Roll (1974) and Black and Blue (1976). Led Zeppelin began to mix elements of world and folk music into their hard rock from Led Zeppelin III (1970) and Led Zeppelin IV (1971). The latter included the track "Stairway to Heaven", which would become the most played song in the history of album-oriented radio. Deep Purple continued to define hard rock, particularly with their album Machine Head (1972), which included the tracks "Highway Star" and "Smoke on the Water". In 1975 guitarist Ritchie Blackmore left, going on to form Rainbow and after the break-up of the band the next year, vocalist David Coverdale formed Whitesnake. 1970 saw The Who release Live at Leeds, often seen as the archetypal hard rock live album, and the following year they released their highly acclaimed album Who's Next, which mixed heavy rock with extensive use of synthesizers. Subsequent albums, including Quadrophenia (1973), built on this sound before Who Are You (1978), their last album before the death of pioneering rock drummer Keith Moon later that year.

What year was the song Stairway to Heaven by Deep Purple produced?
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A:
unanswerable