Waves are generated when energy passes through causing them to move matter through ?

Layers of rock containing fossils, like the layers illustrated here, are most likely composed of rocks.

Which of the following statements is true? a. elements in the last period are radioactive. b. atomic weight is the same as atomic mass. c. elements in the same group have the same number of electron shells. d. atomic number equals the number of neutrons in the nucleus of an atom.

2. how is heavy water different from normal water