Article: Copper has been in use at least 10,000 years, but more than 95% of all copper ever mined and smelted has been extracted since 1900, and more than half was extracted in only the last 24 years. As with many natural resources, the total amount of copper on Earth is vast (around 1014 tons just in the top kilometer of Earth's crust, or about 5 million years' worth at the current rate of extraction). However, only a tiny fraction of these reserves is economically viable, given present-day prices and technologies. Various estimates of existing copper reserves available for mining vary from 25 years to 60 years, depending on core assumptions such as the growth rate. Recycling is a major source of copper in the modern world. Because of these and other factors, the future of copper production and supply is the subject of much debate, including the concept of peak copper, analogous to peak oil.

Question: What percentage of copper has been extracted since 1900?
Ans: 95%


Article: Like many Australian cities, Melbourne has a high dependency on the automobile for transport, particularly in the outer suburban areas where the largest number of cars are bought, with a total of 3.6 million private vehicles using 22,320 km (13,870 mi) of road, and one of the highest lengths of road per capita in the world. The early 20th century saw an increase in popularity of automobiles, resulting in large-scale suburban expansion. By the mid 1950s there was just under 200 passenger vehicles per 1000 people by 2013 there was 600 passenger vehicles per 1000 people. Today it has an extensive network of freeways and arterial roadways used by private vehicles including freight as well as public transport systems including bus and taxis. Major highways feeding into the city include the Eastern Freeway, Monash Freeway and West Gate Freeway (which spans the large West Gate Bridge), whilst other freeways circumnavigate the city or lead to other major cities, including CityLink (which spans the large Bolte Bridge), Eastlink, the Western Ring Road, Calder Freeway, Tullamarine Freeway (main airport link) and the Hume Freeway which links Melbourne and Sydney.

Question: Which freeway spans the large Bolte Bridge?
Ans: CityLink


Article: Although the ECB is governed by European law directly and thus not by corporate law applying to private law companies, its set-up resembles that of a corporation in the sense that the ECB has shareholders and stock capital. Its capital is five billion euros which is held by the national central banks of the member states as shareholders. The initial capital allocation key was determined in 1998 on the basis of the states' population and GDP, but the key is adjustable. Shares in the ECB are not transferable and cannot be used as collateral.

Question: How much does the ECB have as capital?
Ans: five billion euros


Article: Like all major English football clubs, Arsenal have a number of domestic supporters' clubs, including the Arsenal Football Supporters' Club, which works closely with the club, and the Arsenal Independent Supporters' Association, which maintains a more independent line. The Arsenal Supporters' Trust promotes greater participation in ownership of the club by fans. The club's supporters also publish fanzines such as The Gooner, Gunflash and the satirical Up The Arse!. In addition to the usual English football chants, supporters sing "One-Nil to the Arsenal" (to the tune of "Go West").

Question: What is a common chant of Arsenal supporters?
Ans:
One-Nil to the Arsenal