Question: I want to test the ability of students to read a passage and answer questions about it. Could you please come up with a good question for the passage "As of the census of 2010, there were 520,116 people, 229,762 households, and 112,455 families residing in the city. The population density was 2,500.1 inhabitants per square mile (965.3/km). There were 209,609 housing units at an average density of 1,076.7 per square mile (415.7/km). The racial makeup of the city was 69.7% White (down from 94.8% in 1970), 5.0% Black or African-American, 2.7% Native American, 2.9% Asian, 0.2% Pacific Islander, 16.9% from other races, and 3.8% from two or more races. Hispanic or Latino of any race were 41.6% of the population. Non-Hispanic Whites were 47.2% of the population in 2010, down from 72.8% in 1970."?
Answer: What was the average housing density of the city, using the metric system?

Question: I want to test the ability of students to read a passage and answer questions about it. Could you please come up with a good question for the passage "The top ten (eleven in season ten) toured at the end of every season. In the season twelve tour a semi-finalist who won a sing-off was also added to the tour. Kellogg's Pop-Tarts was the sponsor for the first seven seasons, and Guitar Hero was added for the season seven tour. M&M's Pretzel Chocolate Candies was a sponsor of the season nine tour. The season five tour was the most successful tour with gross of over $35 million."?
Answer: Which tour earned less money, nine or five?

Question: I want to test the ability of students to read a passage and answer questions about it. Could you please come up with a good question for the passage "The area's many universities and colleges make Philadelphia a top international study destination, as the city has evolved into an educational and economic hub. With a gross domestic product of $388 billion, Philadelphia ranks ninth among world cities and fourth in the nation. Philadelphia is the center of economic activity in Pennsylvania and is home to seven Fortune 1000 companies. The Philadelphia skyline is growing, with several nationally prominent skyscrapers. The city is known for its arts, culture, and history, attracting over 39 million domestic tourists in 2013. Philadelphia has more outdoor sculptures and murals than any other American city, and Fairmount Park is the largest landscaped urban park in the world. The 67 National Historic Landmarks in the city helped account for the $10 billion generated by tourism. Philadelphia is the birthplace of the United States Marine Corps, and is also the home of many U.S. firsts, including the first library (1731), first hospital (1751) and medical school (1765), first Capitol (1777), first stock exchange (1790), first zoo (1874), and first business school (1881). Philadelphia is the only World Heritage City in the United States."?
Answer:
What is the evidence of Philadelphia's economic status in the state?