Why do fish have scales, and how long is the longest bridge? Try our kids’ quiz

Illustration: Hennie Haworth/The Guardian

1. Agnes, 7, asks: why do fish have scales?

   1. To help keep them warm

   2. To help them swim fast in the water

   3. So that they look beautiful

   4. To protect their bodies

2. Ira, 7, asks: which animal has the loudest cry?

   1. Gorilla

   2. Lion

   3. Howler monkey

   4. Blue whale

3. Matilda, 8, asks: how long is the longest bridge in the world?

   1. 165km

   2. 2,000km

   3. 2km

   4. 22km

4. Catriona, 6, asks: what is the longest a human has ever held their breath for?

   1. For less than 1 minute

   2. For 2 minutes and 7 seconds

   3. For 24 minutes and 37.36 seconds

   4. For 57 minutes and 2 seconds

5. Aaron, 9, asks: how many cities are there in the entire world?

   1. There are around 5,000 cities

   2. There are more than 10,000 cities

   3. There are about 100,000 cities

   4. It’s impossible to count the number of cities there are in the world

Solutions

1:D - Fish have scales to protect their bodies, much like a suit of armour – so if they crash into coral or are attacked by predators, the scales help to defend them., 2:D - Whales have the loudest call of any creature on Earth – the blue whale’s can reach 188 decibels, as loud as a jet plane. Much smaller but just as loud is the tiny tiger pistol shrimp, which doesn’t have a cry but makes a bubble with its claw that causes a shockwave that can reach more than 200 decibels., 3:A - The world’s longest bridge is China’s Danyang-Kunshan Grand Bridge, part of the Beijing-Shanghai high-speed railway. It took four years to build and is almost 165km long., 4:C - In March 2021, in a swimming pool in Croatia, 56-year-old freediver Budimir Šobat broke the world record by holding his breath for almost 25 minutes., 5:B - There are more than 10,000 cities in the world. Tokyo is the largest, with 37 million people living in it. Other huge ones, with more than 20 million people, are Delhi, Shanghai, São Paulo, Mexico City, Cairo, Mumbai, Beijing and Dhaka.

Scores

1. 4 and above.

2. 3 and above.

3. 2 and above.

4. 0 and above.

5. 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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