Problem: The Earth of the early Archean (4,000 to 2,500 million years ago) may have had a different tectonic style. During this time, the Earth's crust cooled enough that rocks and continental plates began to form. Some scientists think because the Earth was hotter, that plate tectonic activity was more vigorous than it is today, resulting in a much greater rate of recycling of crustal material. This may have prevented cratonisation and continent formation until the mantle cooled and convection slowed down. Others argue that the subcontinental lithospheric mantle is too buoyant to subduct and that the lack of Archean rocks is a function of erosion and subsequent tectonic events.
What happened as the Earth's crust cooled following the Archean period?
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Answer: unanswerable


Problem: At the beginning of the Caliphate or Islamic Empire, the reliance on courts initially confined sponsorship and scholarly activities to major centres. Within several centuries, the development of Muslim educational institutions such as the madrasah and masjid eventually introduced such activities to provincial towns and dispersed them across the Islamic legal schools and Sufi orders. In addition to religious subjects, they also taught the "rational sciences," as varied as mathematics, astronomy, astrology, geography, alchemy, philosophy, magic, and occultism, depending on the curriculum of the specific institution in question. The madaris, however, were not centres of advanced scientific study; scientific advances in Islam were usually carried out by scholars working under the patronage of royal courts. During this time,[when?] the Caliphate experienced a growth in literacy, having the highest literacy rate of the Middle Ages, comparable to classical Athens' literacy in antiquity but on a much larger scale. The emergence of the maktab and madrasa institutions played a fundamental role in the relatively high literacy rates of the medieval Islamic world.
Who disapproved of scholars to study natural sciences?
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Answer: unanswerable


Problem: Humans have shown extreme inventiveness in devising clothing solutions to environmental hazards. Examples include: space suits, air conditioned clothing, armor, diving suits, swimsuits, bee-keeper gear, motorcycle leathers, high-visibility clothing, and other pieces of protective clothing. Meanwhile, the distinction between clothing and protective equipment is not always clear-cut—since clothes designed to be fashionable often have protective value and clothes designed for function often consider fashion in their design. Wearing clothes also has social implications. They cover parts of the body that social norms require to be covered, act as a form of adornment, and serve other social purposes.
What do social norms not require of clothes?
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Answer:
unanswerable