Wind erosion is the main cause. And since it is the desert that wind can pick up tiny sand rock particles that slowly grind against the rock. Over time the erosion will give a jagged rock the smooth features as if it had been submerged in a river for the roughly same period of time.
by size, shape and composition?
It means a distant or remote family, meaning they aren't very close.
Explanation:
Using a maps scale most of the time involves some math. Usually you'd take a distance on the map (in inches) and multiply it to whatever that maps scale is, for example 1:500. A maps scale is used to show larger distances on a map in a ratio form to show the real ground distance. Showing 10 miles on a single piece of paper would be rather difficult if there weren't a scale
