Item WE026004: Moving water continuously wears down earth's solid rock layer, which changes the shape of a valley even if you cannot see it happening.

Which of the following statements describes how long it takes for moving water to wear away the solid rock of a valley?

  1. It would take moving water about a hundred years or more to cause any change to the valley, no matter how small.
  2. It would take moving water millions of years or more to cause any change to the valley, no matter how small.
  3. Moving water continuously wears away the solid rock of a valley, which changes the valley even if you can’t see it happening.
  4. Moving water cannot wear away solid rock of a valley.