Input: Greece
By 500 BC, the Persian Empire controlled the Greek city states in Asia Minor and had made territorial gains in the Balkans and Eastern Europe proper as well. Attempts by some of the Greek city-states of Asia Minor to overthrow Persian rule failed, and Persia invaded the states of mainland Greece in 492 BC, but was forced to withdraw after a defeat at the Battle of Marathon in 490 BC. A second invasion by the Persians followed in 480 BC. Despite a heroic resistance at Thermopylae by Spartans and other Greeks led by King Leonidas, and a simultaneous naval engagement at Artemisium,[page needed] Persian forces occupied Athens, which had been evacuated in time, as well as briefly overrunning half of Greece. Following decisive Greek victories in 480 and 479 BC at Salamis, Plataea, and Mycale, the Persians were forced to withdraw for a second time, marking their eventual withdrawal from all of their European territories. Led by Athens and Sparta, the Greek victories in the Greco-Persian Wars are considered a pivotal moment in world history, as the 50 years of peace that followed are known as Golden Age of Athens, the seminal period of ancient Greece that laid many of the foundations of Western civilization.

The battles between the Greeks and Persians are known as what?
Output: Greco-Persian Wars


Input: Article: Houston's highway system has a hub-and-spoke freeway structure serviced by multiple loops. The innermost loop is Interstate 610, which encircles downtown, the medical center, and many core neighborhoods with around a 8-mile (13 km) diameter. Beltway 8 and its freeway core, the Sam Houston Tollway, form the middle loop at a diameter of roughly 23 miles (37 km). A proposed highway project, State Highway 99 (Grand Parkway), will form a third loop outside of Houston, totaling 180 miles in length and making an almost-complete circumference, with the exception of crossing the ship channel. As of June 2014, two of eleven segments of State Highway 99 have been completed to the west of Houston, and three northern segments, totaling 38 miles, are actively under construction and scheduled to open to traffic late in 2015. In addition to the Sam Houston Tollway loop mentioned above, the Harris County Toll Road Authority currently operates four spoke tollways: The Katy Managed Lanes of Interstate 10, the Hardy Toll Road, the Westpark Tollway, and the Fort Bend Parkway Extension. Other spoke roads either planned or under construction include Crosby Freeway, and the future Alvin Freeway.

Now answer this question: What part of the freeway system is Beltway 8?

Output: middle loop


Article: This article covers numbered east-west streets in Manhattan, New York City. Major streets have their own linked articles; minor streets are discussed here. The streets do not run exactly east–west, because the grid plan is aligned with the Hudson River rather than with the cardinal directions. "West" is approximately 29 degrees north of true west.

Question: Which streets have their own linked articles?
Ans: Major streets


Here is a question about this article: At the 2012 census, 59.5% of jobs in the Paris Region were in market services (12.0% in wholesale and retail trade, 9.7% in professional, scientific, and technical services, 6.5% in information and communication, 6.5% in transportation and warehousing, 5.9% in finance and insurance, 5.8% in administrative and support services, 4.6% in accommodation and food services, and 8.5% in various other market services), 26.9% in non-market services (10.4% in human health and social work activities, 9.6% in public administration and defence, and 6.9% in education), 8.2% in manufacturing and utilities (6.6% in manufacturing and 1.5% in utilities), 5.2% in construction, and 0.2% in agriculture.
What is the answer to this question: What industry had the lowest percentage of jobs in Paris of 2012?
****
So... agriculture


The problem: Answer a question about this article:
Patents have been criticized in the developing world, as they are thought to reduce access to existing medicines. Reconciling patents and universal access to medicine would require an efficient international policy of price discrimination. Moreover, under the TRIPS agreement of the World Trade Organization, countries must allow pharmaceutical products to be patented. In 2001, the WTO adopted the Doha Declaration, which indicates that the TRIPS agreement should be read with the goals of public health in mind, and allows some methods for circumventing pharmaceutical monopolies: via compulsory licensing or parallel imports, even before patent expiration.
The Doha Declaration allows for what ways for monopolies to be bypassed?
****
The answer: compulsory licensing or parallel imports


The problem: Answer a question about this article:
Molecules of carbohydrates and fats consist of carbon, hydrogen, and oxygen atoms. Carbohydrates range from simple monosaccharides (glucose, fructose, galactose) to complex polysaccharides (starch). Fats are triglycerides, made of assorted fatty acid monomers bound to a glycerol backbone. Some fatty acids, but not all, are essential in the diet: they cannot be synthesized in the body. Protein molecules contain nitrogen atoms in addition to carbon, oxygen, and hydrogen. The fundamental components of protein are nitrogen-containing amino acids, some of which are essential in the sense that humans cannot make them internally. Some of the amino acids are convertible (with the expenditure of energy) to glucose and can be used for energy production, just as ordinary glucose, in a process known as gluconeogenesis. By breaking down existing protein, the carbon skeleton of the various amino acids can be metabolized to intermediates in cellular respiration; the remaining ammonia is discarded primarily as urea in urine. This occurs normally only during prolonged starvation.
Which element do the amino acids that make up the core component of protein have in common?
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The answer:
nitrogen