Which can associate a suspect and the firing of a gun?
( its not b )
a) markings on the gun's exterior
b) markings on the casing
c) markings on the bullet
d) powder residues

Astable electron arrangement for an atom is one that does not easily change. how is this arrangement arrived at? a. valence electrons are transferred or shared to create a full outer shell of electrons. b. valence electrons are discarded into space to create a full outer shell of electrons. c. protons (positive charge) pair with valence electrons (negative charge) to create a strong bond. d. outer shells with valence electrons are transferred or shared.