Beyond the answers - interesting background to this quiz

The apple, the plague and a year of isolation

Isaac Newton's breakthroughs on gravity are often linked to 1665-1666, when Cambridge closed because of the plague and he retreated to his family's farm in Woolsthorpe. There, away from lectures and deadlines, he worked on motion, optics and mathematics. The falling-apple story is usually told as a neat anecdote, but it points to something real: Newton's insight was not that things fall, but that the same force might govern both an apple and the Moon.

A continent of twelve, not one story

South America has 12 sovereign states, from Brazil and Argentina to Suriname and Uruguay. Brazil alone covers roughly half the continent's land area and is widely considered the most biodiverse country on Earth, home to most of the Amazon rainforest. The Andes, meanwhile, run along the western edge through seven countries, including Ecuador, whose capital Quito sits high in the mountains.

Beethoven's Fifth and the four notes that followed him

Ludwig van Beethoven composed his Fifth Symphony between 1804 and 1808, a period when his hearing was already deteriorating. Its opening motif - often described as "fate knocking at the door" - is one of the most quoted phrases in Western music. What is less known is how much of the symphony grows from that tiny rhythmic cell, which reappears transformed throughout the work.

Capital cities that are not the obvious choice

Riyadh is the capital of Saudi Arabia, but it is far from the only capital in the region that surprises people. Many assume Dubai, in the neighbouring United Arab Emirates, holds that role, when in fact Abu Dhabi does. Riyadh, meanwhile, has grown from a walled oasis town into a metropolis of more than seven million people in less than a century.

Harrisburg, and the puzzle of U.S. state capitals

Pennsylvania's capital is Harrisburg, not Philadelphia or Pittsburgh, which is a common pattern in the United States. Many state capitals were chosen for central location rather than size, precisely so that government would not be dominated by the largest city. That is why Albany, not New York City, leads New York, and Sacramento, not Los Angeles, leads California.