Problem: Glass:

Naturally occurring glass, especially the volcanic glass obsidian, has been used by many Stone Age societies across the globe for the production of sharp cutting tools and, due to its limited source areas, was extensively traded. But in general, archaeological evidence suggests that the first true glass was made in coastal north Syria, Mesopotamia or ancient Egypt. The earliest known glass objects, of the mid third millennium BCE, were beads, perhaps initially created as accidental by-products of metal-working (slags) or during the production of faience, a pre-glass vitreous material made by a process similar to glazing.

What glass-like material is made with a method related to glazing?
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A: faience


Problem: Appalachian Mountains:

The oak forests generally lack the diverse small tree, shrub and herb layers of mesic forests. Shrubs are generally ericaceous, and include the evergreen mountain laurel (Kalmia latifolia), various species of blueberries (Vaccinium spp.), black huckleberry (Gaylussacia baccata), a number of deciduous rhododendrons (azaleas), and smaller heaths such as teaberry (Gaultheria procumbens) and trailing arbutus (Epigaea repens ). The evergreen great rhododendron (Rhododendron maximum) is characteristic of moist stream valleys. These occurrences are in line with the prevailing acidic character of most oak forest soils. In contrast, the much rarer chinquapin oak (Quercus muehlenbergii) demands alkaline soils and generally grows where limestone rock is near the surface. Hence no ericaceous shrubs are associated with it.

What type of soils do most mesic forests have?
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A: unanswerable


Problem: Literature:

Roman histories and biographies anticipated the extensive mediaeval literature of lives of saints and miraculous chronicles, but the most characteristic form of the Middle Ages was the romance, an adventurous and sometimes magical narrative with strong popular appeal. Controversial, religious, political and instructional literature proliferated during the Renaissance as a result of the invention of printing, while the mediaeval romance developed into a more character-based and psychological form of narrative, the novel, of which early and important examples are the Chinese Monkey and the German Faust books.

Modern romance developed into what type of narrative?
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A: unanswerable


Problem: Antibiotics:

Exposure to antibiotics early in life is associated with increased body mass in humans and mouse models. Early life is a critical period for the establishment of the intestinal microbiota and for metabolic development. Mice exposed to subtherapeutic antibiotic treatment (STAT)– with either penicillin, vancomycin, penicillin and vancomycin, or chlortetracycline had altered composition of the gut microbiota as well as its metabolic capabilities. Moreover, research have shown that mice given low-dose penicillin (1 μg/g body weight) around birth and throughout the weaning process had an increased body mass and fat mass, accelerated growth, and increased hepatic expression of genes involved in adipogenesis, compared to controlled mice. In addition, penicillin in combination with a high-fat diet increased fasting insulin levels in mice. However, it is unclear whether or not antibiotics cause obesity in humans. Studies have found a correlation between early exposure of antibiotics (<6 months) and increased body mass (at 10 and 20 months). Another study found that the type of antibiotic exposure was also significant with the highest risk of being overweight in those given macrolides compared to penicillin and cephalosporin. Therefore, there is correlation between antibiotic exposure in early life and obesity in humans, but whether or not there is a causal relationship remains unclear. Although there is a correlation between antibiotic use in early life and obesity, the effect of antibiotics on obesity in humans needs to be weighed against the beneficial effects of clinically indicated treatment with antibiotics in infancy.

Do antibiotics increase the chance of getting fat for humans?
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A:
unclear