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Since June 2007, YouTube's videos have been available for viewing on a range of Apple products. This required YouTube's content to be transcoded into Apple's preferred video standard, H.264, a process that took several months. YouTube videos can be viewed on devices including Apple TV, iPod Touch and the iPhone. In July 2010, the mobile version of the site was relaunched based on HTML5, avoiding the need to use Adobe Flash Player and optimized for use with touch screen controls. The mobile version is also available as an app for the Android platform. In September 2012, YouTube launched its first app for the iPhone, following the decision to drop YouTube as one of the preloaded apps in the iPhone 5 and iOS 6 operating system. According to GlobalWebIndex, YouTube was used by 35% of smartphone users between April and June 2013, making it the third most used app.
When did youtube launch its first app for the iPhone?
A: September 2012

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Agriculture is almost entirely dependent on angiosperms, which provide virtually all plant-based food, and also provide a significant amount of livestock feed. Of all the families of plants, the Poaceae, or grass family (grains), is by far the most important, providing the bulk of all feedstocks (rice, corn — maize, wheat, barley, rye, oats, pearl millet, sugar cane, sorghum). The Fabaceae, or legume family, comes in second place. Also of high importance are the Solanaceae, or nightshade family (potatoes, tomatoes, and peppers, among others), the Cucurbitaceae, or gourd family (also including pumpkins and melons), the Brassicaceae, or mustard plant family (including rapeseed and the innumerable varieties of the cabbage species Brassica oleracea), and the Apiaceae, or parsley family. Many of our fruits come from the Rutaceae, or rue family (including oranges, lemons, grapefruits, etc.), and the Rosaceae, or rose family (including apples, pears, cherries, apricots, plums, etc.).
What are some examples of what the nightshade family provides as the most important group?
A: unanswerable

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The former ten-year moratorium on the construction of new nuclear power plants was the result of a citizens' initiative voted on in 1990 which had passed with 54.5% Yes vs. 45.5% No votes. Plans for a new nuclear plant in the Canton of Bern have been put on hold after the accident at the Fukushima Daiichi power plant in 2011. The Swiss Federal Office of Energy (SFOE) is the office responsible for all questions relating to energy supply and energy use within the Federal Department of Environment, Transport, Energy and Communications (DETEC). The agency is supporting the 2000-watt society initiative to cut the nation's energy use by more than half by the year 2050.
What was the former 10-year moratorium on the construction of nuclear plants the result of?
A: a citizens' initiative

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The use of the term Länder (Lands) dates back to the Weimar Constitution of 1919. Before this time, the constituent states of the German Empire were called Staaten (States). Today, it is very common to use the term Bundesland (Federal Land). However, this term is not used officially, neither by the constitution of 1919 nor by the Basic Law (Constitution) of 1949. Three Länder call themselves Freistaaten (Free States, which is the old-fashioned German expression for Republic), Bavaria (since 1919), Saxony (originally since 1919 and again since 1990), and Thuringia (since 1994). There is little continuity between the current states and their predecessors of the Weimar Republic with the exception of the three free states, and the two city-states of Hamburg and Bremen.
Before 1919 what were the German states called?
A:
Staaten