Interesting question, Reesha.
Water flows downhill. For instance, after it rains the water will
collect in low valleys, not on hilltops. If we expand our picture to
include the entire Earth, water will settle as close to the center of
the Earth as it can. So the high areas will stick out above the waters
of the oceans.
There is not enough liquid water to cover all the high areas on the
Earth, so these places above the water is the land on which we live. If
the Earth's surface was perfectly flat, then the entire earth would be
covered in water.
I hope this answers your question.
math dan
(published on 10/22/2007)