Input: Black people
From the late 19th century, the South used a colloquial term, the one-drop rule, to classify as black a person of any known African ancestry. This practice of hypodescent was not put into law until the early 20th century. Legally the definition varied from state to state. Racial definition was more flexible in the 18th and 19th centuries before the American Civil War. For instance, President Thomas Jefferson held persons who were legally white (less than 25% black) according to Virginia law at the time, but, because they were born to slave mothers, they were born into slavery, according to the principle of partus sequitur ventrem, which Virginia adopted into law in 1662.

When was racial definition more flexible?
Output: 18th and 19th centuries

Input: Black people
Black people is a term used in certain countries, often in socially based systems of racial classification or of ethnicity, to describe persons who are perceived to be dark-skinned compared to other given populations. As such, the meaning of the expression varies widely both between and within societies, and depends significantly on context. For many other individuals, communities and countries, "black" is also perceived as a derogatory, outdated, reductive or otherwise unrepresentative label, and as a result is neither used nor defined.

Can the term "black people" have different meanings?
Output: the meaning of the expression varies widely both between and within societies, and depends significantly on context.

Input: Treaty
Muhammad also ordered another siege on the Banu Qurayza during the Invasion of Banu Qurayza, because according to Muslim tradition he had been ordered to do so by the angel Gabriel. Al-Waqidi claims Muhammad had a treaty with the tribe which was torn apart. Stillman and Watt deny the authenticity of al-Waqidi. Al-Waqidi has been frequently criticized by Muslim writers, who claim that he is unreliable. 600-900 members of the Banu Qurayza were beheaded after they surrendered (according to Tabari and Ibn Hisham). Another source says all Males and 1 woman beheaded (according to Sunni Hadith). Two Muslims were killed

What angel, according to Muslim tradition, ordered Muhammad to order a siege on the Banu Qurayza?
Output: Gabriel

Input: Copper
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]

When did Natural bronze start to be used by the general public?
Output:
5500 BC