What is the longest river in the world? Try our kids’ quiz

Illustration: Hennie Haworth/The Guardian

1. Arthur, 7, asks: what is the longest river in the world?

   1. The Zambezi

   2. The Thames

   3. The Nile or the Amazon

   4. The Orinoco

2. Connie, 5, asks: where do flamingos get their colour from?

   1. The sun turns their feathers pink

   2. The water flamingos swim in is pink

   3. The food they eat has a pigment in it that turns their feathers pink

   4. The freshwater is rich in iron which turns their feathers pink

3. Rosie, 6, asks: how heavy is the Queen’s Imperial State Crown?

   1. 500g, about the same as half a litre of water

   2. About 1kg

   3. 2.1kg, about the same as a bag of 12 apples

   4. 5kg, about the same as five bags of sugar

4. Jacob, 7, asks: how old is the moon?

   1. It is not possible to work out how old the moon is

   2. The moon is 25.3m years old

   3. The moon is 1bn years old

   4. The moon is 4.425bn years old

5. Daisy, 9, asks: what are egg yolks made of?

   1. Egg yolks are made of yolker, a fatty substance a bit like curdled cheese

   2. Egg yolks are made of calcium and salt

   3. Egg yolks are made of protein, fat, lecithin and other things

   4. Egg yolks are made of partially digested food

Solutions

1:C - According to Guinness World Records, the longest river in the world is the Nile. It is 6,695km long from its main source, Lake Victoria in east central Africa, to the farthest stream, in Burundi. Others do not agree and say the Amazon is longer – it is hard to measure accurately because scientists argue over its start and end points., 2:C - Flamingos are not born pink. They get their pink colour from their food. Beta-carotene is an orange pigment found in things flamingos eat, including algae and brine shrimp. If humans ate only carrots, slowly their skin might go a shade of orange, but you’d need to eat a LOT of carrots., 3:B - The Queen’s Imperial State Crown weighs more than 1kg. It is made of gold and has 2,868 diamonds, four rubies, 11 emeralds, 17 sapphires and 269 pearls., 4:D - Until 2020, the moon was reckoned to be more than 4.5bn years old, but then scientists using a new way of measuring found it is 85m years younger than that., 5:C - Egg yolks are made of protein, fat, an emulsifier called lecithin and carotenoid from the hens’ food which gives yolks their colour.

Scores

1. 5 and above.

2. 4 and above.

3. 3 and above.

4. 2 and above.

5. 0 and above.

6. 1 and above.

Molly Oldfield hosts Everything Under the Sun, a weekly podcast answering children’s questions, out now as a book.

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