Beyond the answers - interesting background to this quiz

The mountain range that stretches across seven countries

The Andes are usually associated with Peru, but they actually run through seven South American countries, from Venezuela in the north down to Chile and Argentina. They form the longest continental mountain range in the world, and their high plateaus and peaks have shaped the cultures, climates and farming traditions of the region for thousands of years. Patagonia, meanwhile, sits at the southern end of the continent and is shared between Chile and Argentina, a vast region of steppe, glaciers and windswept plains.

Vitamins that need fat to be absorbed

Vitamin A belongs to the group of fat-soluble vitamins, along with D, E and K. This means the body absorbs them best when they are eaten with some fat, and it can store them in the liver and fatty tissue for later use. Water-soluble vitamins such as C and the B group work differently: they dissolve in water, are not stored in large amounts, and any excess is usually passed out of the body.

The longest mountain range is mostly underwater

The Mid-Atlantic Ridge is the longest mountain range on Earth, but most of it lies beneath the Atlantic Ocean. It runs roughly from the Arctic down toward the southern Atlantic, formed where tectonic plates pull apart and new seafloor is created. Only a small fraction of it rises above the water, which is why it rarely comes to mind when people picture the world's great mountain chains.

A shuttle named Columbia

Columbia was the first space shuttle to fly in orbit, launching in 1981, and it took its name from an American sailing ship that explored the Pacific Northwest in the 1790s. Five shuttles flew over the programme's three decades. The fleet also included Challenger, Discovery, Atlantis and Endeavour, and between them they carried hundreds of astronauts and helped build the International Space Station.

Why the 20th century is easy to date

World War II is a reliable anchor for the 20th century: it was fought between 1939 and 1945 and reshaped borders, economies and international institutions around the world. Thomas Edison's phonograph and the first electric motors, by contrast, belong to the 19th century, which is why they make useful distractors in a history question.