Beyond the answers - interesting background to this quiz

A play written as a warning

Arthur Miller wrote "The Crucible" in the early 1950s, using the Salem witch trials of 1692 as a mirror for the anti-communist hearings then gripping America. Miller himself was later called before the House Un-American Activities Committee and refused to name colleagues, a stance that cost him professionally. The play endures because its subject - fear turning neighbours into accusers - keeps finding new settings.

The shuttle that changed how we watched launches

Challenger was one of NASA's reusable orbiters, and its 1986 loss, shortly after lift-off, became one of the most publicised disasters in spaceflight history. What made it especially painful was the audience: schoolchildren across the United States were watching live because a teacher, Christa McAuliffe, was aboard. The tragedy reshaped how NASA handled risk and public communication.

Melville's whale that first flopped

Herman Melville published "Moby-Dick" in 1851 to modest sales and mixed reviews, and it was largely forgotten by the time he died. Its revival came decades later, when critics began treating the book's digressions on whaling, philosophy and obsession as strengths rather than obstacles. Today it is a cornerstone of American literature, though its author never lived to see that verdict.

Two capitals that are not the obvious choice

Morocco's capital is Rabat, not the far larger Casablanca, and Japan's is Tokyo rather than the former imperial seat of Kyoto. This pattern is common: countries often keep a political capital separate from their commercial or cultural hub, sometimes deliberately, to spread administration away from a dominant metropolis. It is a useful reminder that the city everyone has heard of is not always the one running the country.

Caffeine, by the numbers

Caffeine's formula, C8H10N4O2, tells you it is built from carbon, hydrogen, nitrogen and oxygen - a small molecule with an outsized reputation. It occurs naturally in coffee beans, tea leaves and cacao, and works by blocking adenosine, a compound that helps make us feel sleepy. The result is the familiar lift, along with the equally familiar crash when it wears off.