Beyond the answers - interesting background to this quiz

A gift that arrived in pieces

The Statue of Liberty was dedicated in 1886, a decade after France first proposed the idea as a gift marking the centenary of American independence. Designed by sculptor Frédéric Auguste Bartholdi with an internal framework engineered by Gustave Eiffel, the statue was built in France and shipped to New York in crates. The copper skin is only a few millimetres thick, which is why the whole structure could be dismantled, transported across the Atlantic and reassembled on Bedloe's Island, now Liberty Island.

Malta's money has changed more than once

Malta adopted the euro in 2008, replacing the Maltese lira, which had itself replaced the pound. As a small island economy with strong tourism and financial services, Malta benefits from sharing a currency with its largest trading partners in the eurozone. For visitors, the practical upshot is simple: no awkward currency exchange between the airport and the hotel, and prices that are easy to compare with elsewhere in Europe.

The lake that fills a collapsed mountain

Crater Lake in Oregon is the deepest lake in the United States, and it sits inside a caldera formed when Mount Mazama collapsed after a massive eruption roughly 7,700 years ago. With no rivers flowing in or out, the lake is fed almost entirely by rain and snow, which helps give it its famous clarity and deep blue colour. It is also one of the clearest bodies of water in the world.

Venice and its many nicknames

Venice has been called the Queen of the Adriatic for centuries, a nod to the maritime power it once wielded across the region. The city built its wealth on trade routes linking Europe with the eastern Mediterranean and beyond, and its lagoon setting made it both defensible and prosperous. Other labels, like La Serenissima, the most serene republic, reflect the same pride in a city that was for centuries an independent republic.

Hydrogen peroxide is a simple but useful molecule

Hydrogen peroxide has the formula H2O2: two hydrogen atoms and two oxygen atoms, one more oxygen than water. That extra oxygen makes it a useful oxidising agent, which is why dilute solutions are used for cleaning and disinfecting. In high concentrations it becomes hazardous, and in nature it breaks down quickly into water and oxygen.