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The roots of hard rock can be traced back to the 1950s, particularly electric blues, which laid the foundations for key elements such as a rough declamatory vocal style, heavy guitar riffs, string-bending blues-scale guitar solos, strong beat, thick riff-laden texture, and posturing performances. Electric blues guitarists began experimenting with hard rock elements such as driving rhythms, distorted guitar solos and power chords in the 1950s, evident in the work of Memphis blues guitarists such as Joe Hill Louis, Willie Johnson, and particularly Pat Hare, who captured a "grittier, nastier, more ferocious electric guitar sound" on records such as James Cotton's "Cotton Crop Blues" (1954). Other antecedents include Link Wray's instrumental "Rumble" in 1958, and the surf rock instrumentals of Dick Dale, such as "Let's Go Trippin'" (1961) and "Misirlou" (1962).
What city's blues style produced hard rock precursors in electric blues?
A: Memphis

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The Legislative Assembly of the Federal District is formed, as it is the case in all legislatures in Mexico, by both single-seat and proportional seats, making it a system of parallel voting. The Federal District is divided into 40 electoral constituencies of similar population which elect one representative by first-past-the-post plurality (FPP), locally called "uninominal deputies". The Federal District as a whole constitutes a single constituency for the parallel election of 26 representatives by proportionality (PR) with open-party lists, locally called "plurinominal deputies".
What is the local government of Mexico City called?
A: The Legislative Assembly of the Federal District

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Aristotle wrote in his book Meteorology about an Antarctic region in c. 350 B.C. Marinus of Tyre reportedly used the name in his unpreserved world map from the 2nd century A.D. The Roman authors Hyginus and Apuleius (1–2 centuries A.D.) used for the South Pole the romanized Greek name polus antarcticus, from which derived the Old French pole antartike (modern pôle antarctique) attested in 1270, and from there the Middle English pol antartik in a 1391 technical treatise by Geoffrey Chaucer (modern Antarctic Pole).
What did authors Hyginus and Apuleious call the South Pole?
A: polus antarcticus

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One of the most spectacular examples of obligate mutualism is between the siboglinid tube worms and symbiotic bacteria that live at hydrothermal vents and cold seeps. The worm has no digestive tract and is wholly reliant on its internal symbionts for nutrition. The bacteria oxidize either hydrogen sulfide or methane, which the host supplies to them. These worms were discovered in the late 1980s at the hydrothermal vents near the Galapagos Islands and have since been found at deep-sea hydrothermal vents and cold seeps in all of the world's oceans.
From where do the host obtain the hydrogen sulfide or methane?
A:
unanswerable