Problem: Internet service provider:

Just as their customers pay them for Internet access, ISPs themselves pay upstream ISPs for Internet access. An upstream ISP usually has a larger network than the contracting ISP or is able to provide the contracting ISP with access to parts of the Internet the contracting ISP by itself has no access to.

What does an upstream ISP provide for an ISP?
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A: access to parts of the Internet the contracting ISP by itself has no access to

Problem: In 1948, the point-contact transistor was independently invented by German physicists Herbert Matare and Heinrich Welker while working at the Compagnie des Freins et Signaux, a Westinghouse subsidiary located in Paris. Matare had previous experience in developing crystal rectifiers from silicon and germanium in the German radar effort during World War II. Using this knowledge, he began researching the phenomenon of "interference" in 1947. By June 1948, witnessing currents flowing through point-contacts, Matare produced consistent results using samples of germanium produced by Welker, similar to what Bardeen and Brattain had accomplished earlier in December 1947. Realizing that Bell Labs' scientists had already invented the transistor before them, the company rushed to get its "transistron" into production for amplified use in France's telephone network.
When did Heinrich Welker start researching electronics?
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Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Miami has six major causeways that span over Biscayne Bay connecting the western mainland, with the eastern barrier islands along the Atlantic Ocean. The Rickenbacker Causeway is the southernmost causeway and connects Brickell to Virginia Key and Key Biscayne. The Venetian Causeway and MacArthur Causeway connect Downtown with South Beach. The Julia Tuttle Causeway connects Midtown and Miami Beach. The 79th Street Causeway connects the Upper East Side with North Beach. The northernmost causeway, the Broad Causeway, is the smallest of Miami's six causeways, and connects North Miami with Bal Harbour.
What causeway is closest to the south?
A: unanswerable

Context and question: Between 1996 and 2004, the population of the city increased by 4.9 per centthe tenth biggest increase in England. In 2005 the Government Statistics stated that Southampton was the third most densely populated city in the country after London and Portsmouth respectively. Hampshire County Council expects the city's population to grow by around a further two per cent between 2006 and 2013, adding around another 4,200 to the total number of residents. The highest increases are expected among the elderly.
By what percentage did the population of Southampton increase from 1996 to 2004?
Answer: 4.9

Question: To feel or see the difference between aspirated and unaspirated sounds, one can put a hand or a lit candle in front of one's mouth, and say pin [pn] and then spin [spn]. One should either feel a puff of air or see a flicker of the candle flame with pin that one does not get with spin. In most dialects of English, the initial consonant is aspirated in pin and unaspirated in spin.
Is there an answer to this question: What would you see when you use your hand to see the difference between aspirated and unaspirated sounds?

Answer: unanswerable

Question: Mark Z. Jacobson, professor of civil and environmental engineering at Stanford University and director of its Atmosphere and Energy Program says producing all new energy with wind power, solar power, and hydropower by 2030 is feasible and existing energy supply arrangements could be replaced by 2050. Barriers to implementing the renewable energy plan are seen to be "primarily social and political, not technological or economic". Jacobson says that energy costs with a wind, solar, water system should be similar to today's energy costs.
Is there an answer to this question: What is a barrier to implementing the renewable energy plan?

Answer:
social and political