Mystery #3Tier 2-3weather / air
Why do clouds float when they're full of water?
A big cloud can hold hundreds of tonnes of water, as much as a herd of elephants. Water is heavier than air, so by rights a cloud should crash straight down. Why does it just hang there instead?

Your guess
What's your hunch about how a cloud holding tonnes of water stays up in the air?
There's no single magic word to type, have a go in your own words, then reveal the answer to see how close you got.
Make a guess to unlock the hints and the answer.