Problem: Hellenistic period:

After Cassander's death in 298 BCE, however, Demetrius, who still maintained a sizable loyal army and fleet, invaded Macedon, seized the Macedonian throne (294) and conquered Thessaly and most of central Greece (293-291). He was defeated in 288 BC when Lysimachus of Thrace and Pyrrhus of Epirus invaded Macedon on two fronts, and quickly carved up the kingdom for themselves. Demetrius fled to central Greece with his mercenaries and began to build support there and in the northern Peloponnese. He once again laid siege to Athens after they turned on him, but then struck a treaty with the Athenians and Ptolemy, which allowed him to cross over to Asia minor and wage war on Lysimachus' holdings in Ionia, leaving his son Antigonus Gonatas in Greece. After initial successes, he was forced to surrender to Seleucus in 285 and later died in captivity. Lysimachus, who had seized Macedon and Thessaly for himself, was forced into war when Seleucus invaded his territories in Asia minor and was defeated and killed in 281 BCE at the Battle of Corupedium, near Sardis. Seleucus then attempted to conquer Lysimachus' European territories in Thrace and Macedon, but he was assassinated by Ptolemy Ceraunus ("the thunderbolt"), who had taken refuge at the Seleucid court and then had himself acclaimed as king of Macedon. Ptolemy was killed when Macedon was invaded by Gauls in 279, his head stuck on a spear and the country fell into anarchy. Antigonus II Gonatas invaded Thrace in the summer of 277 and defeated a large force of 18,000 Gauls. He was quickly hailed as king of Macedon and went on to rule for 35 years.

What year was Seleucus killed?
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A: 281 BCE

Problem: The first real progress toward a modern understanding of nervous function, though, came from the investigations of Luigi Galvani, who discovered that a shock of static electricity applied to an exposed nerve of a dead frog could cause its leg to contract. Since that time, each major advance in understanding has followed more or less directly from the development of a new technique of investigation. Until the early years of the 20th century, the most important advances were derived from new methods for staining cells. Particularly critical was the invention of the Golgi stain, which (when correctly used) stains only a small fraction of neurons, but stains them in their entirety, including cell body, dendrites, and axon. Without such a stain, brain tissue under a microscope appears as an impenetrable tangle of protoplasmic fibers, in which it is impossible to determine any structure. In the hands of Camillo Golgi, and especially of the Spanish neuroanatomist Santiago Ramon y Cajal, the new stain revealed hundreds of distinct types of neurons, each with its own unique dendritic structure and pattern of connectivity.
The tool that was invented to stain only a small fractions of neurons was called what?
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Answer: the Golgi stain

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
In May and June 1835, the area which is now central and northern Melbourne was explored by John Batman, a leading member of the Port Phillip Association in Van Diemen's Land (now known as Tasmania), who claimed to have negotiated a purchase of 600,000 acres (2,400 km2) with eight Wurundjeri elders. Batman selected a site on the northern bank of the Yarra River, declaring that "this will be the place for a village". Batman then returned to Launceston in Tasmania. In early August 1835 a different group of settlers, including John Pascoe Fawkner, left Launceston on the ship Enterprize. Fawkner was forced to disembark at Georgetown, Tasmania, because of outstanding debts. The remainder of the party continued and arrived at the mouth of the Yarra River on 15 August 1835. On 30 August 1835 the party disembarked and established a settlement at the site of the current Melbourne Immigration Museum. Batman and his group arrived on 2 September 1835 and the two groups ultimately agreed to share the settlement.
Tasmania was formerly known as what?
A: Van Diemen's Land

Context and question: Organized crime has long been associated with New York City, beginning with the Forty Thieves and the Roach Guards in the Five Points in the 1820s. The 20th century saw a rise in the Mafia, dominated by the Five Families, as well as in gangs, including the Black Spades. The Mafia presence has declined in the city in the 21st century.
The Forth Thieves and Roach Guards were two gangs that operated in what area of New York in the 1820s?
Answer: the Five Points

Question: The name evolved during the Middle Ages from Gallaecia, sometimes written Galletia, to Gallicia. In the 13th century, with the written emergence of the Galician language, Galiza became the most usual written form of the name of the country, being replaced during the 15th and 16th centuries by the current form, Galicia, which coincides with the Castilian Spanish name. The historical denomination Galiza became popular again during the end of the 19th and the first three-quarters of the 20th century, being still used with some frequency today, although not by the Xunta de Galicia, the local devolved government. The Royal Galician Academy, the institution responsible for regulating the Galician language, whilst recognizing it as a legitimate current denomination, has stated that the only official name of the country is Galicia.
Is there an answer to this question: When did it get its modern spelling?

Answer: 15th and 16th centuries

Question: Football is largely considered the Nigeria's national sport and the country has its own Premier League of football. Nigeria's national football team, known as the "Super Eagles", has made the World Cup on five occasions 1994, 1998, 2002, 2010, and most recently in 2014. In April 1994, the Super Eagles ranked 5th in the FIFA World Rankings, the highest ranking achieved by an African football team. They won the African Cup of Nations in 1980, 1994, and 2013, and have also hosted the U-17 & U-20 World Cup. They won the gold medal for football in the 1996 Summer Olympics (in which they beat Argentina) becoming the first African football team to win gold in Olympic Football.
Is there an answer to this question: Which years did Nigeria win the African Cup of Nations?

Answer:
1980, 1994, and 2013