Answer:
I'm having a hard time with this, I keep confusing myself but hopefully this example will help at least to get an idea:
"12 cm
Explanation:
We're pouring 12 litres of water into a container that is 40cm long and 25cm wide. Let's see how big the bottom of the container is:
40cm×25cm=1000cm2
1 litre of water fills 1000cm3, and so it would rise 1 cm (we divide the volume of the water by the surface area to arrive at the height):
1000cm31000cm2=1cm
12 litres of water can then be seen to rise 12 cm:
12×1000cm31000cm2=12cm"
