Which statement best explains why the overal change on an atom is zero

An atom has a neutral overall charge because it has the same amount of electrons as protons. Protons and neutrons have the equivalent mass. Electrons have such a little mass that this can normally be considered as zero.

Explanation:

indicate valleys, hills, steepness and gentleness of slopes.

explanation:

contour lines on a map indicate elevation, or depth. numeric notations on contour lines refer to the level of elevation, or height about sea level.