<span>..has evaporated from all the water sources around the world (streams, rivers, ponds, seas, oceans etc).
It is am established fact that the quantity of water present on the Earth has remained constant from the beginning of time. At any given point in time it may exist in one of its three forms i.e.ice, water or water vapor but there is no variation in its total quantity (hydrological cycle).</span>
It would be easier to put an image instead of explaining it. Here you are!
R = Red
r = white
RR = 25% - 25% chance of red
Rr = 50% - 50% chance of pink
rr = 25% - 25% chance of white