Article: 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.

Question: What was obsidian used to make in prehistoric times?
Ans: cutting tools


Article: The classification of birds is a contentious issue. Sibley and Ahlquist's Phylogeny and Classification of Birds (1990) is a landmark work on the classification of birds, although it is frequently debated and constantly revised. Most evidence seems to suggest the assignment of orders is accurate, but scientists disagree about the relationships between the orders themselves; evidence from modern bird anatomy, fossils and DNA have all been brought to bear on the problem, but no strong consensus has emerged. More recently, new fossil and molecular evidence is providing an increasingly clear picture of the evolution of modern bird orders. The most recent effort is drawn above and is based on whole genome sequencing of 48 representative species.

Question: What do scientists tend to agree on?
Ans: the assignment of orders is accurate


Article: However, not all highest courts are named as such. Civil law states do not tend to have singular highest courts. Additionally, the highest court in some jurisdictions is not named the "Supreme Court", for example, the High Court of Australia; this is because decisions by the High Court could formerly be appealed to the Privy Council. On the other hand, in some places the court named the "Supreme Court" is not in fact the highest court; examples include the New York Supreme Court, the Supreme Courts of several Canadian provinces/territories and the former Supreme Court of Judicature of England and Wales, which are all superseded by higher Courts of Appeal.

Question: To which body can decisions made by this specific high court be appealed?
Ans: the Privy Council


Article: Most copper is mined or extracted as copper sulfides from large open pit mines in porphyry copper deposits that contain 0.4 to 1.0% copper. Examples include Chuquicamata in Chile, Bingham Canyon Mine in Utah, United States and El Chino Mine in New Mexico, United States. According to the British Geological Survey, in 2005, Chile was the top mine producer of copper with at least one-third world share followed by the United States, Indonesia and Peru. Copper can also be recovered through the in-situ leach process. Several sites in the state of Arizona are considered prime candidates for this method. The amount of copper in use is increasing and the quantity available is barely sufficient to allow all countries to reach developed world levels of usage.

Question: What is the name of the process being considered in Arizona that allows copper to be recovered?
Ans:
in-situ leach process