it is unusable because many people do not waste water and which is a good thing to save water.
get the minerals,nutrients and other healthy nutrients from the unusable to make it usable water..
70% or 80% of water covers the earths surface
about 30%
My mom
3% of the earths water, is fresh water
45%
3% is fresh, but 1% is for drinking.
14
2%
Roughly 75% of Earths Surface is covered by water. (including the Oceans, lakes and land Ice).
we use about 1/4 of earth's water