The problem: Answer a question about this article:
For centuries, various peoples in modern-day Nigeria traded overland with traders from North Africa. Cities in the area became regional centres in a broad network of trade routes that spanned western, central and northern Africa. In the 16th century, Spanish and Portuguese explorers were the first Europeans to begin significant, direct trade with peoples of modern-day Nigeria, at the port they named Lagos and in Calabar. Europeans traded goods with peoples at the coast; coastal trade with Europeans also marked the beginnings of the Atlantic slave trade. The port of Calabar on the historical Bight of Biafra (now commonly referred to as the Bight of Bonny) become one of the largest slave trading posts in West Africa in the era of the transatlantic slave trade. Other major slaving ports in Nigeria were located in Badagry, Lagos on the Bight of Benin and on Bonny Island on the Bight of Biafra. The majority of those enslaved and taken to these ports were captured in raids and wars. Usually the captives were taken back to the conquerors' territory as forced labour; after time, they were sometimes acculturated and absorbed into the conquerors' society. A number of slave routes were established throughout Nigeria linking the hinterland areas with the major coastal ports. Some of the more prolific slave traders were linked with the Oyo Empire in the southwest, the Aro Confederacy in the southeast and the Sokoto Caliphate in the north.
What region has Nigeria traded with for centuries?
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The answer: North Africa

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By 1960 African Americans comprised 16.45% of the state's population. It was not until after the mid-1960s and passage of the Voting Rights Act of 1965 that they were able to vote in full again, but new devices, such as at-large commission city governments, had been adopted in several jurisdictions to limit their political participation. Former Gov. Winfield Dunn and former U.S. Sen. Bill Brock wins in 1970 helped make the Republican Party competitive among whites for the statewide victory. Tennessee has selected governors from different parties since 1970. Increasingly the Republican Party has become the party of white conservatives.
Which Republican Senator's 1970 victory showed the Republican Party's renewed competitiveness in Tennessee?
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The answer: Bill Brock

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The incentive to use 100% renewable energy, for electricity, transport, or even total primary energy supply globally, has been motivated by global warming and other ecological as well as economic concerns. The Intergovernmental Panel on Climate Change has said that there are few fundamental technological limits to integrating a portfolio of renewable energy technologies to meet most of total global energy demand. In reviewing 164 recent scenarios of future renewable energy growth, the report noted that the majority expected renewable sources to supply more than 17% of total energy by 2030, and 27% by 2050; the highest forecast projected 43% supplied by renewables by 2030 and 77% by 2050. Renewable energy use has grown much faster than even advocates anticipated. At the national level, at least 30 nations around the world already have renewable energy contributing more than 20% of energy supply. Also, Professors S. Pacala and Robert H. Socolow have developed a series of "stabilization wedges" that can allow us to maintain our quality of life while avoiding catastrophic climate change, and "renewable energy sources," in aggregate, constitute the largest number of their "wedges."
Who developed a series of stabilization wedges?
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The answer: Professors S. Pacala and Robert H. Socolow

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In July 2007, American business magnate and investor Warren Buffett's holding company Berkshire Hathaway bought an Israeli company, Iscar, its first non-U.S. acquisition, for $4 billion. Since the 1970s, Israel has received military aid from the United States, as well as economic assistance in the form of loan guarantees, which now account for roughly half of Israel's external debt. Israel has one of the lowest external debts in the developed world, and is a net lender in terms of net external debt (the total value of assets vs. liabilities in debt instruments owed abroad), which in December 2015[update] stood at a surplus of US$118 billion.
When did United States begin to provide foreign aid to Israel?
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The answer:
1970s