Question: While LEDs have the advantage over fluorescent lamps that they do not contain mercury, they may contain other hazardous metals such as lead and arsenic. Regarding the toxicity of LEDs when treated as waste, a study published in 2011 stated: "According to federal standards, LEDs are not hazardous except for low-intensity red LEDs, which leached Pb [lead] at levels exceeding regulatory limits (186 mg/L; regulatory limit: 5). However, according to California regulations, excessive levels of copper (up to 3892 mg/kg; limit: 2500), lead (up to 8103 mg/kg; limit: 1000), nickel (up to 4797 mg/kg; limit: 2000), or silver (up to 721 mg/kg; limit: 500) render all except low-intensity yellow LEDs hazardous."
Try to answer this question if possible:  What dangerous metal can non-LEDs contain?
Answer: unanswerable
Question: The revived Georgian style that emerged in Britain at the beginning of the 20th century is usually referred to as Neo-Georgian; the work of Edwin Lutyens includes many examples. Versions of the Neo-Georgian style were commonly used in Britain for certain types of urban architecture until the late 1950s, Bradshaw Gass & Hope's Police Headquarters in Salford of 1958 being a good example. In both the United States and Britain, the Georgian style is still employed by architects like Quinlan Terry Julian Bicknell and Fairfax and Sammons for private residences.
Try to answer this question if possible: Neo-Georgain style was common in Britain until the end of which decade?
Answer: 1950s
Question: On October 2, the Popular Front formally launched its political platform at a two-day congress. Väljas attended, gambling that the front could help Estonia become a model of economic and political revival, while moderating separatist and other radical tendencies. On November 16, 1988, the Supreme Soviet of the Estonian SSR adopted a declaration of national sovereignty under which Estonian laws would take precedence over those of the Soviet Union. Estonia's parliament also laid claim to the republic's natural resources including land, inland waters, forests, mineral deposits, and to the means of industrial production, agriculture, construction, state banks, transportation, and municipal services within the territory of Estonia's borders.
Try to answer this question if possible: Whose laws would take precedence according to the declaration of national sovereignty?
Answer: Estonian
Question: In 2011, documents obtained by WikiLeaks revealed that Beyoncé was one of many entertainers who performed for the family of Libyan ruler Muammar Gaddafi. Rolling Stone reported that the music industry was urging them to return the money they earned for the concerts; a spokesperson for Beyoncé later confirmed to The Huffington Post that she donated the money to the Clinton Bush Haiti Fund. Later that year she became the first solo female artist to headline the main Pyramid stage at the 2011 Glastonbury Festival in over twenty years, and was named the highest-paid performer in the world per minute.
Try to answer this question if possible: In which year was reports about Beyonce performing for Muammar Gaddafi surface?
Answer:
2011