Problem: Samurai:

A samurai could divorce his wife for a variety of reasons with approval from a superior, but divorce was, while not entirely nonexistent, a rare event. A wife's failure to produce a son was cause for divorce, but adoption of a male heir was considered an acceptable alternative to divorce. A samurai could divorce for personal reasons, even if he simply did not like his wife, but this was generally avoided as it would embarrass the person who had arranged the marriage. A woman could also arrange a divorce, although it would generally take the form of the samurai divorcing her. After a divorce samurai had to return the betrothal money, which often prevented divorces.

How common was divorce for samurai?
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A: rare

Problem: Hellenistic period:

The Greek kingdom of Bactria began as a breakaway satrapy of the Seleucid empire, which, because of the size of the empire, had significant freedom from central control. Between 255-246 BCE, the governor of Bactria, Sogdiana and Margiana (most of present-day Afghanistan), one Diodotus, took this process to its logical extreme and declared himself king. Diodotus II, son of Diodotus, was overthrown in about 230 BC by Euthydemus, possibly the satrap of Sogdiana, who then started his own dynasty. In c. 210 BC, the Greco-Bactrian kingdom was invaded by a resurgent Seleucid empire under Antiochus III. While victorious in the field, it seems Antiochus came to realise that there were advantages in the status quo (perhaps sensing that Bactria could not be governed from Syria), and married one of his daughters to Euthydemus's son, thus legitimising the Greco-Bactria dynasty. Soon afterwards the Greco-Bactrian kingdom seems to have expanded, possibly taking advantage of the defeat of the Parthian king Arsaces II by Antiochus.

What leader overthrew Diodotus II?
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A: Euthydemus

Problem: Frederic Chopin:

Chopin's qualities as a pianist and composer were recognized by many of his fellow musicians. Schumann named a piece for him in his suite Carnaval, and Chopin later dedicated his Ballade No. 2 in F major to Schumann. Elements of Chopin's music can be traced in many of Liszt's later works. Liszt later transcribed for piano six of Chopin's Polish songs. A less fraught friendship was with Alkan, with whom he discussed elements of folk music, and who was deeply affected by Chopin's death.

What piece of Chopin's work was dedicated to Schumann?
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A: Ballade No. 2 in F major

Problem: British Empire:

Most former British colonies and protectorates are among the 53 member states of the Commonwealth of Nations, a non-political, voluntary association of equal members, comprising a population of around 2.2 billion people. Sixteen Commonwealth realms voluntarily continue to share the British monarch, Queen Elizabeth II, as their head of state. These sixteen nations are distinct and equal legal entities the United Kingdom, Australia, Canada, New Zealand, Papua New Guinea, Antigua and Barbuda, The Bahamas, Barbados, Belize, Grenada, Jamaica, Saint Kitts and Nevis, Saint Lucia, Saint Vincent and the Grenadines, Solomon Islands and Tuvalu.

How many Commonwealth nations still consider the British Queen their head of state?
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A:
Sixteen