the surface of the earth is made of 70% ocean
earth's_surface is not 70_water. composition_of_earth is 35_percent_iron. earth has surface earth's_surface is 70_water. composition_of_earth is not 28_percent_oxygen. earth has not surface composition_of_earth is 0.4_percent_aluminum. composition_of_earth is 13_percent_silicon. composition_of_earth is not 35_percent_iron. composition_of_earth is 28_percent_oxygen.