Beyond the answers - interesting background to this quiz

A cartoon baby who arrived with a cave-age twist

Pebbles Flintstone was introduced in the early 1960s as the newborn daughter of Fred and Wilma, giving the show a new generation of Stone Age gags. Her name fits the series' habit of turning prehistoric rock into everyday objects and names, from dinosaur-powered cranes to stone newspapers. Later storylines paired her with Bamm-Bamm Rubble, and the two eventually married in animated television films.

Two rivers, two very different records

The Nile is traditionally cited as the world's longest river, running roughly 6,650 kilometres through northeastern Africa before reaching the Mediterranean. The Amazon carries by far the greater volume of water and drains the largest rainforest on Earth, which is why the two are often compared rather than simply ranked. The Mekong tells a third story: it rises on the Tibetan Plateau and flows through China, Myanmar, Laos, Thailand, Cambodia and Vietnam, supporting fisheries that feed millions.

Why noble metals stay shiny

Platinum, silver and gold are called noble metals because they resist oxidation and corrosion, which is why they keep their lustre and are prized in jewellery and electronics. Zinc sits on the other side of that line: it reacts readily with air and moisture, forming a dull grey layer. That very reactivity is useful, since zinc coatings sacrifice themselves to protect the steel underneath, a process known as galvanising.

Estonia's money and the euro's northern edge

Estonia adopted the euro in 2011, becoming the first of the three Baltic states to join the currency. Before that it used the kroon, a name shared with several Nordic currencies and linked to the word for crown. The ruble belongs to Russia, while the lek is used in Albania, a reminder of how many distinct currencies circulate across a relatively small continent.