Beyond the answers - interesting background to this quiz

A desert smaller than many city parks

The Carcross Desert in Yukon, Canada, covers roughly 2.6 square kilometres, which is why it is often called the smallest desert in the world. It is not a true desert in the strictest sense: it is a collection of sandy dunes left behind by glacial lakes, kept bare by strong winds and a dry local climate. Its unusual setting, surrounded by boreal forest and mountains, makes it a popular stop for travellers on the way to Alaska.

Bones built for more than standing

The femur, or thigh bone, is the longest and strongest bone in the human body, and it has to be. It carries most of your body weight with every step and can withstand forces several times greater than your own mass. The name comes from the Latin word for thigh, and the same root shows up in the word "femoral", used in anatomy and medicine.

A Christmas Carol and the Victorian conscience

Charles Dickens wrote A Christmas Carol in 1843, at a time when poverty and harsh working conditions were pressing social issues in Britain. The story of Ebenezer Scrooge, a miser transformed by three ghostly visits, was written quickly and published in time for Christmas. It became one of Dickens's most beloved works and helped shape modern ideas about generosity and the festive season.

Counting like a Roman

Roman numerals use combinations of letters, with I, V, X, L, C, D and M standing for different values. The number 24 is written XXIV: two tens, then one less than five. The subtractive rule, where a smaller numeral before a larger one means subtraction, is why IV means four rather than six. Roman numerals still appear on clock faces, building dates and film credits.

A century shaped by a pandemic

The Spanish flu pandemic occurred in the 20th century, spreading across the world between 1918 and 1920. Despite the name, it did not originate in Spain; the label stuck partly because wartime censorship elsewhere limited reporting, while Spanish newspapers covered the outbreak freely. It is estimated to have infected a large share of the global population and remains one of the deadliest pandemics in recorded history.