The problem: Answer a question about this article:
In 1854 president Antonio Lopez de Santa Anna enlarged the area of the Federal District almost eightfold from the original 220 to 1,700 km2 (80 to 660 sq mi), annexing the rural and mountainous areas to secure the strategic mountain passes to the south and southwest to protect the city in event of a foreign invasion. (The MexicanAmerican War had just been fought.) The last changes to the limits of the Federal District were made between 1898 and 1902, reducing the area to the current 1,479 km2 (571 sq mi) by adjusting the southern border with the state of Morelos. By that time, the total number of municipalities within the Federal District was twenty-two.
What is the current area of Mexico City?
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The answer: 1,479 km2 (571 sq mi)

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Even prior to the penetration of European interests, Southeast Asia was a critical part of the world trading system. A wide range of commodities originated in the region, but especially important were spices such as pepper, ginger, cloves, and nutmeg. The spice trade initially was developed by Indian and Arab merchants, but it also brought Europeans to the region. First Spaniards (Manila galleon) and Portuguese, then the Dutch, and finally the British and French became involved in this enterprise in various countries. The penetration of European commercial interests gradually evolved into annexation of territories, as traders lobbied for an extension of control to protect and expand their activities. As a result, the Dutch moved into Indonesia, the British into Malaya and parts of Borneo, the French into Indochina, and the Spanish and the US into the Philippines.
Who developed the spice trade initially?
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The answer: Indian and Arab merchants

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Differences in pain perception and tolerance thresholds are associated with, among other factors, ethnicity, genetics, and sex. People of Mediterranean origin report as painful some radiant heat intensities that northern Europeans describe as nonpainful. And Italian women tolerate less intense electric shock than Jewish or Native American women. Some individuals in all cultures have significantly higher than normal pain perception and tolerance thresholds. For instance, patients who experience painless heart attacks have higher pain thresholds for electric shock, muscle cramp and heat.
Along with with ethnicity and genetics, what is the other factor associated with differences in pain perception?
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The answer: sex

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In 2008, Houston received top ranking on Kiplinger's Personal Finance Best Cities of 2008 list, which ranks cities on their local economy, employment opportunities, reasonable living costs, and quality of life. The city ranked fourth for highest increase in the local technological innovation over the preceding 15 years, according to Forbes magazine. In the same year, the city ranked second on the annual Fortune 500 list of company headquarters, first for Forbes magazine's Best Cities for College Graduates, and first on their list of Best Cities to Buy a Home. In 2010, the city was rated the best city for shopping, according to Forbes.
Where did Houston place for Fortune 500 companies?
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The answer:
second