Question: Why did the Nok culture die off about 200 AD on the Jos Plateau? Passage 1:While working as a model after completing her master's degree, Reed was invited to a WWE tryout in 2011. She signed a developmental contract with WWE in March 2011 and was assigned to Florida Championship Wrestling (FCW). The following month, she debuted under the ring name Brandi, accompanying Lucky Cannon at an FCW house show. On May 12, she began working as a ring announcer on weekly episodes of Superstars. On July 11, Reed also began announcing duties on NXT, under the ring name Eden Stiles. She filled in as the ring announcer for SmackDown on the July 15 and November 11 episodes. Her only match took place on July 16 at FCW Summer SlamaRama, where she was involved in a battle royal, which was won by Sonia. In December, at her request, Reed was released from her WWE contract.
 Passage 2:The Nok culture thrived from approximately 1,500 BC to about 200 AD on the Jos Plateau in north and central Nigeria and produced life-sized terracotta figures that include human heads, human figures, and animals. Iron smelting furnaces at Taruga, a Nok site, date from around 600 BC. The Nok culture is thought to have begun smelting iron by 600-500 BC and possibly some centuries earlier. Kainji Dam excavations revealed iron-working by the 2nd century BC. Evidence of iron smelting has also been excavated at sites in the Nsukka region of southeast Nigeria in what is now Igboland: dating to 2,000 BC at the site of Lejja (Uzomaka 2009) and to 750 BC and at the site of Opi (Holl 2009). The transition from Neolithic times to the Iron Age apparently was achieved indigenously without intermediate bronze production. Others have suggested that the technology moved west from the Nile Valley, although the Iron Age in the Niger River valley and the forest region appears to predate the introduction of metallurgy in the upper savanna by more than 800 years. The earliest iron technology in West Africa has also been found to be contemporary with or predate that of the Nile valley and North Africa, and some archaeologists believe that iron metallurgy was likely developed independently in sub-Saharan West Africa.
 Passage 3:Born in Braintree, Massachusetts, Adams spent much of his youth in Europe, where his father served as a diplomat. After returning to the United States, Adams established a successful legal practice in Boston. In 1794, President George Washington appointed Adams as the U.S. ambassador to the Netherlands, and Adams would serve in high-ranking diplomatic posts until 1801, when Thomas Jefferson took office as president. Federalist leaders in Massachusetts arranged for Adams's election to the United States Senate in 1802, but Adams broke with the Federalist Party over foreign policy and was denied re-election. In 1809, Adams was appointed as the U.S. ambassador to Russia by President James Madison, a member of the Democratic-Republican Party. Adams held diplomatic posts for the duration of Madison's presidency, and he served as part of the American delegation that negotiated an end to the War of 1812. In 1817, newly-elected President James Monroe selected Adams as his Secretary of State. In that role, Adams negotiated the Adams–Onís Treaty, which provided for the American acquisition of Florida. He also helped formulate the Monroe Doctrine, which became a key tenet of U.S. foreign policy.

Output: 2