Input: Sumer
Though women were protected by late Sumerian law and were able to achieve a higher status in Sumer than in other contemporary civilizations, the culture was male-dominated. The Code of Ur-Nammu, the oldest such codification yet discovered, dating to the Ur-III "Sumerian Renaissance", reveals a glimpse at societal structure in late Sumerian law. Beneath the lu-gal ("great man" or king), all members of society belonged to one of two basic strata: The "lu" or free person, and the slave (male, arad; female geme). The son of a lu was called a dumu-nita until he married. A woman (munus) went from being a daughter (dumu-mi), to a wife (dam), then if she outlived her husband, a widow (numasu) and she could then remarry.

How many strata existed in Sumerian society?
Output: two

Input: Article: The development of writing enabled knowledge to be stored and communicated across generations with much greater fidelity. Combined with the development of agriculture, which allowed for a surplus of food, it became possible for early civilizations to develop, because more time and effort could be devoted to tasks (other than food production) than hunter-gatherers or early subsistence farmers had available. This surplus allowed a community to support individuals who did things other than work towards bare survival. These other tasks included systematic studies of nature, study of written information gathered and recorded by others, and often of adding to that body of information.

Now answer this question: What advancement aided in spreading knowledge across generations?

Output: The development of writing

Article: The just-noticeable difference (jnd) (the threshold at which a change is perceived) depends on the tone's frequency content. Below 500 Hz, the jnd is about 3 Hz for sine waves, and 1 Hz for complex tones; above 1000 Hz, the jnd for sine waves is about 0.6% (about 10 cents). The jnd is typically tested by playing two tones in quick succession with the listener asked if there was a difference in their pitches. The jnd becomes smaller if the two tones are played simultaneously as the listener is then able to discern beat frequencies. The total number of perceptible pitch steps in the range of human hearing is about 1,400; the total number of notes in the equal-tempered scale, from 16 to 16,000 Hz, is 120.

Question: The jnd is typically tested by?
Ans: playing two tones in quick succession

Here is a question about this article: Some people argue that elevators began as simple rope or chain hoists (see Traction elevators below). An elevator is essentially a platform that is either pulled or pushed up by a mechanical means. A modern-day elevator consists of a cab (also called a "cage", "carriage" or "car") mounted on a platform within an enclosed space called a shaft or sometimes a "hoistway". In the past, elevator drive mechanisms were powered by steam and water hydraulic pistons or by hand. In a "traction" elevator, cars are pulled up by means of rolling steel ropes over a deeply grooved pulley, commonly called a sheave in the industry. The weight of the car is balanced by a counterweight. Sometimes two elevators are built so that their cars always move synchronously in opposite directions, and are each other's counterweight.
What is the answer to this question: Elevator drive mechanisms have, in the past been, powered by what?
****
So... steam and water hydraulic pistons or by hand

The problem: Answer a question about this article:
San Diego was ranked as the 20th-safest city in America in 2013 by Business Insider. According to Forbes magazine, San Diego was the ninth-safest city in the top 10 list of safest cities in the U.S. in 2010. Like most major cities, San Diego had a declining crime rate from 1990 to 2000. Crime in San Diego increased in the early 2000s. In 2004, San Diego had the sixth lowest crime rate of any U.S. city with over half a million residents. From 2002 to 2006, the crime rate overall dropped 0.8%, though not evenly by category. While violent crime decreased 12.4% during this period, property crime increased 1.1%. Total property crimes per 100,000 people were lower than the national average in 2008.
What happened to the crime rate in San Diego between 1990 and 2000?
****
The answer: San Diego had a declining crime rate from 1990 to 2000

The problem: Answer a question about this article:
New Haven is the birthplace of former president George W. Bush, who was born when his father, former president George H. W. Bush, was living in New Haven while a student at Yale. In addition to being the site of the college educations of both Presidents Bush, as Yale students, New Haven was also the temporary home of former presidents William Howard Taft, Gerald Ford, and Bill Clinton, as well as Secretary of State John Kerry. President Clinton met his wife, former U.S. Secretary of State Hillary Rodham Clinton, while the two were students at Yale Law School. Former vice presidents John C. Calhoun and Dick Cheney also studied in New Haven (although the latter did not graduate from Yale). Before the 2008 election, the last time there was not a person with ties to New Haven and Yale on either major party's ticket was 1968. James Hillhouse, a New Haven native, served as President pro tempore of the United States Senate in 1801.
Which former U.S. president have been born in New Haven?
****
The answer:
George W. Bush