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Copper occurs naturally as native copper and was known to some of the oldest civilizations on record. It has a history of use that is at least 10,000 years old, and estimates of its discovery place it at 9000 BC in the Middle East; a copper pendant was found in northern Iraq that dates to 8700 BC. There is evidence that gold and meteoric iron (but not iron smelting) were the only metals used by humans before copper. The history of copper metallurgy is thought to have followed the following sequence: 1) cold working of native copper, 2) annealing, 3) smelting, and 4) the lost wax method. In southeastern Anatolia, all four of these metallurgical techniques appears more or less simultaneously at the beginning of the Neolithic c. 7500 BC. However, just as agriculture was independently invented in several parts of the world, copper smelting was invented locally in several different places. It was probably discovered independently in China before 2800 BC, in Central America perhaps around 600 AD, and in West Africa about the 9th or 10th century AD. Investment casting was invented in 4500–4000 BC in Southeast Asia and carbon dating has established mining at Alderley Edge in Cheshire, UK at 2280 to 1890 BC. Ötzi the Iceman, a male dated from 3300–3200 BC, was found with an axe with a copper head 99.7% pure; high levels of arsenic in his hair suggest his involvement in copper smelting. Experience with copper has assisted the development of other metals; in particular, copper smelting led to the discovery of iron smelting. Production in the Old Copper Complex in Michigan and Wisconsin is dated between 6000 and 3000 BC. Natural bronze, a type of copper made from ores rich in silicon, arsenic, and (rarely) tin, came into general use in the Balkans around 5500 BC.[citation needed]
Copper smelting resulted in the development of what other metal smelting?
A: iron smelting

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The state of Chihuahua is the largest state in the country and is known as El Estado Grande (The Big State); it accounts for 12.6% of the land of Mexico. The area is landlocked by the states of Sonora to the west, Sinaloa to the south-west, Durango to the south, and Coahuila to the east, and by the U.S. states of Texas to the northeast and New Mexico to the north. The state is made up of three geologic regions: Mountains, Plains-Valleys, and Desert, which occur in large bands from west to east. Because of the different geologic regions there are contrasting climates and ecosystems.
What percentage of the country does it make up?
A: 12.6%

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Tajiks began to be conscripted into the Soviet Army in 1939 and during World War II around 260,000 Tajik citizens fought against Germany, Finland and Japan. Between 60,000(4%) and 120,000(8%) of Tajikistan's 1,530,000 citizens were killed during World War II. Following the war and Stalin's reign attempts were made to further expand the agriculture and industry of Tajikistan. During 1957–58 Nikita Khrushchev's Virgin Lands Campaign focused attention on Tajikistan, where living conditions, education and industry lagged behind the other Soviet Republics. In the 1980s, Tajikistan had the lowest household saving rate in the USSR, the lowest percentage of households in the two top per capita income groups, and the lowest rate of university graduates per 1000 people. By the late 1980s Tajik nationalists were calling for increased rights. Real disturbances did not occur within the republic until 1990. The following year, the Soviet Union collapsed, and Tajikistan declared its independence.
What was not developing as fast as other Soviet Republics?
A: living conditions, education and industry

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The city management and urban policy program was ranked first in the nation, and the special education program second, by U.S. News & World Report's 2016 rankings. USN&WR also ranked several programs in the top 25 among U.S. universities.
In what tier did a number of KU's programs rank in 2016?
A:
the top 25