Problem: Selenizza is a naturally occurring solid hydrocarbon bitumen found in the native asphalt deposit of Selenice, in Albania, the only European asphalt mine still in use. The rock asphalt is found in the form of veins, filling cracks in a more or less horizontal direction. The bitumen content varies from 83% to 92% (soluble in carbon disulphide), with a penetration value near to zero and a softening point (ring & ball) around 120 C. The insoluble matter, consisting mainly of silica ore, ranges from 8% to 17%.
To what location is Selenizza bitumen native?
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Answer: Selenice, in Albania

Problem: The patron saint of Palermo is Santa Rosalia, who is widely revered. On 14 July, people in Palermo celebrate the annual Festino, the most important religious event of the year. The Festino is a procession which goes through the main street of Palermo to commemorate the miracle attributed to Santa Rosalia who, it is believed, freed the city from the Black Death in 1624. Her remains were discovered in a cave on Monte Pellegrino, and her remains were carried around the city three times, banishing the plague. There is a sanctuary marking the spot where her remains were found which can be reached via a scenic bus ride from the city.
Who banished the plague from the city before dying themselves?
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Answer: unanswerable

Problem: Color in glass may be obtained by addition of electrically charged ions (or color centers) that are homogeneously distributed, and by precipitation of finely dispersed particles (such as in photochromic glasses). Ordinary soda-lime glass appears colorless to the naked eye when it is thin, although iron(II) oxide (FeO) impurities of up to 0.1 wt% produce a green tint, which can be viewed in thick pieces or with the aid of scientific instruments. Further FeO and Cr2O3 additions may be used for the production of green bottles. Sulfur, together with carbon and iron salts, is used to form iron polysulfides and produce amber glass ranging from yellowish to almost black. A glass melt can also acquire an amber color from a reducing combustion atmosphere. Manganese dioxide can be added in small amounts to remove the green tint given by iron(II) oxide. When used in art glass or studio glass is colored using closely guarded recipes that involve specific combinations of metal oxides, melting temperatures and 'cook' times. Most colored glass used in the art market is manufactured in volume by vendors who serve this market although there are some glassmakers with the ability to make their own color from raw materials.
What can prevent a green color in glass?
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Answer:
Manganese dioxide