the ground water since only 23 percent of the ground water was used by the <span>United States as water source compared to the fresh water which is 77 percent. It is said to be that since 2005 US utilized 349,000 gallons per day. hope this helps!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!</span>
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.
Answer:
Mercury is the smallest planet, but its surface gravity is about the same as that of the much larger Mars because Mercury is more dense.
hope this helped good luck!
