Problem: Alloy:

At a certain temperature, (usually between 1,500 F (820 C) and 1,600 F (870 C), depending on carbon content), the base metal of steel undergoes a change in the arrangement of the atoms in its crystal matrix, called allotropy. This allows the small carbon atoms to enter the interstices of the iron crystal, diffusing into the iron matrix. When this happens, the carbon atoms are said to be in solution, or mixed with the iron, forming a single, homogeneous, crystalline phase called austenite. If the steel is cooled slowly, the iron will gradually change into its low temperature allotrope. When this happens the carbon atoms will no longer be soluble with the iron, and will be forced to precipitate out of solution, nucleating into the spaces between the crystals. The steel then becomes heterogeneous, being formed of two phases; the carbon (carbide) phase cementite, and ferrite. This type of heat treatment produces steel that is rather soft and bendable. However, if the steel is cooled quickly the carbon atoms will not have time to precipitate. When rapidly cooled, a diffusionless (martensite) transformation occurs, in which the carbon atoms become trapped in solution. This causes the iron crystals to deform intrinsically when the crystal structure tries to change to its low temperature state, making it very hard and brittle.

What changes when steel reaches 870F?
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A: unanswerable

Problem: Education:

Higher education, also called tertiary, third stage, or postsecondary education, is the non-compulsory educational level that follows the completion of a school such as a high school or secondary school. Tertiary education is normally taken to include undergraduate and postgraduate education, as well as vocational education and training. Colleges and universities mainly provide tertiary education. Collectively, these are sometimes known as tertiary institutions. Individuals who complete tertiary education generally receive certificates, diplomas, or academic degrees.

What is another name for the fourth stage of education?
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A: unanswerable

Problem: Norfolk Island:

Norfolk Island is the only non-mainland Australian territory to have achieved self-governance. The Norfolk Island Act 1979, passed by the Parliament of Australia in 1979, is the Act under which the island was governed until the passing of the Norfolk Island Legislation Amendment Act 2015. The Australian government maintains authority on the island through an Administrator, currently Gary Hardgrave. From 1979 to 2015, a Legislative Assembly was elected by popular vote for terms of not more than three years, although legislation passed by the Australian Parliament could extend its laws to the territory at will, including the power to override any laws made by the assembly.

Who is the future administrator of Norfolk Island?
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A: unanswerable

Problem: Communications in Somalia:

After forming partnerships with multinational corporations such as Sprint, ITT and Telenor, these firms now offer the cheapest and clearest phone calls in Africa. These Somali telecommunication companies also provide services to every city, town and hamlet in Somalia. There are presently around 25 mainlines per 1,000 persons, and the local availability of telephone lines (tele-density) is higher than in neighboring countries; three times greater than in adjacent Ethiopia. Prominent Somali telecommunications companies include Somtel Network, Golis Telecom Group, Hormuud Telecom, Somafone, Nationlink, Netco, Telcom and Somali Telecom Group. Hormuud Telecom alone grosses about $40 million a year. Despite their rivalry, several of these companies signed an interconnectivity deal in 2005 that allows them to set prices, maintain and expand their networks, and ensure that competition does not get out of control.

what is another word for availability of telephone lines?
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A:
tele-density