Wind

In this photo we lit a empty tea bag on fire and
when the heat got to the bottom the tea bag lifted.

Wind 

Why does wind exist?

Wind exist because the air heats up and gets warm.
Why we need wind?We need wind because if we didn't have wind we wouldn't have as much rain or the oxygen wouldn't spread around the air.
Way's wind help us:Wind helps us dry our clothes,makes the sail boats go.

In this picture you can see that when you heat up
Potassium Permanganate it rise to the top because
of all the heat.  

These are the crystal like thing that we put
in the hot water.