Beyond the answers - interesting background to this quiz

A currency named after a shape

Japan's yen has one of the most literal names in finance: the word means "round object" or "circle", a nod to the shape of the coins. It was formally adopted in 1871 as part of the Meiji government's push to modernise the country's monetary system, replacing a confusing patchwork of feudal-era coins and paper notes. The yen has been a major reserve currency for decades, and its banknotes are periodically redesigned to stay ahead of counterfeiters.

A vote that ended decades of division

Nelson Mandela's election as president in 1994 was the climax of South Africa's first fully democratic vote, in which citizens of all races could participate. He had spent 27 years in prison, much of it on Robben Island, before his release in 1990. Rather than seeking a second term, he stepped down in 1999, setting an example of voluntary relinquishment of power that remains rare in global politics.

Tallinn's medieval heart

Tallinn, Estonia's capital, sits on the Gulf of Finland and has one of the best-preserved medieval old towns in Europe. Its cobbled streets, city walls and watchtowers date largely from the 13th to 16th centuries, when the city was a thriving member of the Hanseatic League. Today the same city is known for its digital government and tech sector - a striking contrast with its stone ramparts.

The astronomer who kept asking why

Johannes Kepler did not simply describe where the planets appear in the sky; he searched for the mathematical rules behind their motion. Working from the extraordinarily precise observations of Tycho Brahe, he showed that planets move in ellipses rather than perfect circles, and that they speed up as they approach the Sun. His three laws of planetary motion later gave Isaac Newton the foundation for his theory of gravitation.

Penguins at the extreme

The emperor penguin is not just the largest living penguin species - it also breeds in some of the harshest conditions on Earth. Emperors lay a single egg during the Antarctic winter, and the male balances it on his feet under a fold of skin for roughly two months while fasting. Temperatures during this period can drop well below -40°C, with wind speeds high enough to make survival a genuine feat.