Beyond the answers - interesting background to this quiz

A French novelist who thought about animals

Robert Merle, the author of The Day of the Dolphin, was a French writer perhaps best known for his historical saga Fortune de France. His 1967 novel imagines dolphins trained to communicate with humans, and it was later adapted into a film. Merle often used fiction to probe how humans treat other intelligent beings.

The one piece of apparatus both gymnasts share

Artistic gymnastics has separate apparatus lists for men and women, but the floor exercise appears on both. Men perform their floor routines without music, while women's floor routines are set to music and emphasise choreography. The other events - balance beam, uneven bars, pommel horse, rings and vault - belong to one side or the other.

Two capitals, two very different neighbourhoods

Freetown, the capital of Sierra Leone, sits on the Atlantic coast and grew out of a settlement for freed slaves in the late eighteenth century. Yerevan, capital of Armenia, is one of the oldest continuously inhabited cities in the world and lies near the Turkish border. Neither is the largest city of a neighbouring country, which is what makes the wrong options tempting.

A river that crosses a continent

The Amazon flows through South America, draining a basin that covers parts of Brazil, Peru, Colombia and several other countries. It carries more water than any other river on Earth, and its rainforest is home to an extraordinary share of the planet's species. Its location is a classic geography quiz staple for good reason.

From whitepaper to household word

Bitcoin was introduced in 2008 by a person or group using the name Satoshi Nakamoto, and it became the first widely known cryptocurrency. It relies on a public ledger called the blockchain, maintained by a network of computers rather than a central bank. Whatever your view of it, it has changed how people talk about money.