Problem: Law of the United States:

In turn, according to Kozinski's analysis, the contemporary rule of binding precedent became possible in the U.S. in the nineteenth century only after the creation of a clear court hierarchy (under the Judiciary Acts), and the beginning of regular verbatim publication of U.S. appellate decisions by West Publishing. The rule gradually developed, case-by-case, as an extension of the judiciary's public policy of effective judicial administration (that is, in order to efficiently exercise the judicial power). The rule of precedent is generally justified today as a matter of public policy, first, as a matter of fundamental fairness, and second, because in the absence of case law, it would be completely unworkable for every minor issue in every legal case to be briefed, argued, and decided from first principles (such as relevant statutes, constitutional provisions, and underlying public policies), which in turn would create hopeless inefficiency, instability, and unpredictability, and thereby undermine the rule of law.

How is a court hierarchy established?
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A: the Judiciary Acts

Problem: Botany:

Botany, also called plant science(s) or plant biology, is the science of plant life and a branch of biology. A botanist or plant scientist is a scientist who specializes in this field. The term "botany" comes from the Ancient Greek word (botane) meaning "pasture", "grass", or "fodder"; is in turn derived from (boskein), "to feed" or "to graze". Traditionally, botany has also included the study of fungi and algae by mycologists and phycologists respectively, with the study of these three groups of organisms remaining within the sphere of interest of the International Botanical Congress. Nowadays, botanists study approximately 400,000 species of living organisms of which some 260,000 species are vascular plants and about 248,000 are flowering plants.

What is a plant scientist called?
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A: A botanist

Problem: Russian Soviet Federative Socialist Republic:

The final name for the republic during the Soviet era was adopted by the Russian Constitution of 1937, which renamed it the Russian Soviet Federative Socialist Republic.

What was Soviet Russia not called as of 1937?
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A: unanswerable

Problem: Light-emitting diode:

In the US, one kilowatt-hour (3.6 MJ) of electricity currently causes an average 1.34 pounds (610 g) of CO
2 emission. Assuming the average light bulb is on for 10 hours a day, a 40-watt bulb will cause 196 pounds (89 kg) of CO
2 emission per year. The 6-watt LED equivalent will only cause 30 pounds (14 kg) of CO
2 over the same time span. A building's carbon footprint from lighting can therefore be reduced by 85% by exchanging all incandescent bulbs for new LEDs if a building previously used only incandescent bulbs.

How much can a building's carbon footprint be reduced by switching to non-LEDs?
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A:
unanswerable