Problem: BeiDou Navigation Satellite System:

In February 2007, the fourth and last satellite of the BeiDou-1 system, BeiDou-1D (sometimes called BeiDou-2A, serving as a backup satellite), was sent up into space. It was reported that the satellite had suffered from a control system malfunction but was then fully restored.

According to reports, the satellite had issues with what system and was never fully restored?
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A: unanswerable


Problem: Portugal spearheaded European exploration of the world and the Age of Discovery. Prince Henry the Navigator, son of King João I, became the main sponsor and patron of this endeavour. During this period, Portugal explored the Atlantic Ocean, discovering several Atlantic archipelagos like the Azores, Madeira, and Cape Verde, explored the African coast, colonized selected areas of Africa, discovered an eastern route to India via the Cape of Good Hope, discovered Brazil, explored the Indian Ocean, established trading routes throughout most of southern Asia, and sent the first direct European maritime trade and diplomatic missions to China and Japan.
Which three Atlantic archipelagos did Portugal discover?
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Answer: Azores, Madeira, and Cape Verde


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
San Diego is served by the San Diego Trolley light rail system, by the SDMTS bus system, and by Coaster and Amtrak Pacific Surfliner commuter rail; northern San Diego county is also served by the Sprinter light rail line. The Trolley primarily serves downtown and surrounding urban communities, Mission Valley, east county, and coastal south bay. A planned Mid-Coast extension of the Trolley will operate from Old Town to University City and the University of California, San Diego along the I-5 Freeway, with planned operation by 2018. The Amtrak and Coaster trains currently run along the coastline and connect San Diego with Los Angeles, Orange County, Riverside, San Bernardino, and Ventura via Metrolink and the Pacific Surfliner. There are two Amtrak stations in San Diego, in Old Town and the Santa Fe Depot downtown. San Diego transit information about public transportation and commuting is available on the Web and by dialing "511" from any phone in the area.
What areas of San Diego are primarily served by the trolley?
A: downtown and surrounding urban communities


Context and question: The most common, and most purely linguistic, criterion is that of mutual intelligibility: two varieties are said to be dialects of the same language if being a speaker of one variety confers sufficient knowledge to understand and be understood by a speaker of the other; otherwise, they are said to be different languages. However, this definition becomes problematic in the case of dialect continua, in which it may be the case that dialect B is mutually intelligible with both dialect A and dialect C but dialects A and C are not mutually intelligible with each other. In this case the criterion of mutual intelligibility makes it impossible to decide whether A and C are dialects of the same language or not. Cases may also arise in which a speaker of dialect X can understand a speaker of dialect Y, but not vice versa; the mutual intelligibility criterion flounders here as well.
What trait is the most common way of determining if languages are dialects?
Answer: mutual intelligibility


Question: Lower Manhattan is the third-largest central business district in the United States and is home to the New York Stock Exchange, on Wall Street, and the NASDAQ, at 165 Broadway, representing the world's largest and second largest stock exchanges, respectively, when measured both by overall average daily trading volume and by total market capitalization of their listed companies in 2013. Investment banking fees on Wall Street totaled approximately $40 billion in 2012, while in 2013, senior New York City bank officers who manage risk and compliance functions earned as much as $324,000 annually. In fiscal year 2013–14, Wall Street's securities industry generated 19% of New York State's tax revenue. New York City remains the largest global center for trading in public equity and debt capital markets, driven in part by the size and financial development of the U.S. economy.:31–32 In July 2013, NYSE Euronext, the operator of the New York Stock Exchange, took over the administration of the London interbank offered rate from the British Bankers Association. New York also leads in hedge fund management; private equity; and the monetary volume of mergers and acquisitions. Several investment banks and investment mangers headquartered in Manhattan are important participants in other global financial centers.:34–35 New York is also the principal commercial banking center of the United States.
Is there an answer to this question: The New York Stock exchange is located where in NYC?

Answer: Wall Street


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
23rd Street is another main numbered street in Manhattan. It begins at FDR Drive and ends at Eleventh Avenue. Its length is 3.1 km/1.9m. It has two-way travel. On 23rd Street there are five local subway stations:
How many local subway stations are on 23rd Street?
A:
five