Beyond the answers - interesting background to this quiz

The voyage that crossed an invisible line

James Cook's second expedition, begun in 1772, was the first to sail south of the Antarctic Circle, though the ships never sighted the Antarctic continent itself. Cook commanded two vessels, Resolution and Adventure, and made several crossings of the circle over the following years. Ice and fog repeatedly blocked the way, and Cook returned convinced that any southern land would be cold, barren and largely useless. His reports nonetheless encouraged later sealers and explorers to push further south.

A fish built for bursts of speed

The sailfish is widely regarded as the fastest fish in the ocean, capable of short bursts that have been measured at close to 100 kilometres per hour. Its name comes from the tall, sail-like dorsal fin it raises when excited or hunting. Like marlins and swordfish, it belongs to the billfish family and uses its long, pointed bill to slash at schools of smaller fish. Such extreme speed is sustainable only briefly, since it demands enormous energy.

Mozart's final stage work

The Magic Flute premiered in Vienna in 1791, the year Mozart died, and he conducted the first performances himself. The libretto, by Emanuel Schikaneder, blends fairy-tale adventure with Masonic symbolism, and the opera mixes spoken dialogue with arias and ensembles. Its Queen of the Night aria is famous for its punishing coloratura passages, while the bird-catcher Papageno supplies much of the comedy. Within months of the premiere Mozart was dead, and the work soon became one of the most performed operas in the world.

Hemingway's sea, and the river that dwarfs all others

The Old Man and the Sea, published in 1952, tells of an ageing Cuban fisherman, Santiago, and his long struggle with a giant marlin. The book helped secure Hemingway the Nobel Prize in Literature in 1954. The Amazon, meanwhile, carries more water than any other river and drains the largest basin on Earth, covering roughly two-fifths of South America. Its network of tributaries reaches into several countries, and the river's discharge into the Atlantic is so vast that it measurably dilutes the ocean's salinity far offshore.