I attached the image. Options for 1st blank:
A. each atom and the shared electrons
B. the nuclei of the two atoms
C. the valence electrons of the two atoms

Options for 2nd blank:
A. energy levels
B. protons and neutrons
C. valence electrons

When balancing a chemical equation:

Which sentence about particles in matter is true? a. atoms are present in solids and liquids but not in gases. b. the particles of matter are in constant motion. c. the same kinds of atoms are found in different elements. d. when a solid changes to a liquid, the sizes of the particles change.

Which fact represents evidence for the big bang theory?