(a) No person, corporation, or firm shall knowingly sell, supply, deliver, or give possession or control of a firearm to any person within any of the classes prohibited by Chapter 2 (commencing with Section 29800) or Chapter 3 (commencing with Section 29900) of Division 9.
(b) No person, corporation, or dealer shall sell, supply, deliver, or give possession or control of a firearm to anyone whom the person, corporation, or dealer has cause to believe is within any of the classes prohibited by Chapter 2 (commencing with Section 29800) or Chapter 3 (commencing with Section 29900) of Division 9 of this title, or Section 8100 or 8103 of the Welfare and Institutions Code.