(a) No person may sell cigarettes at retail using a cigarette vending machine unless a sign with the message “SURGEON GENERAL’S WARNING: SMOKING BY PREGNANT WOMEN MAY RESULT IN FETAL INJURY, PREMATURE BIRTH, AND LOW BIRTH WEIGHT” is displayed in plain view on the machine.
     (b) No person may sell or offer to sell cigarettes at retail unless a sign with the message “SURGEON GENERAL’S WARNING: SMOKING BY PREGNANT WOMEN MAY RESULT IN FETAL INJURY, PREMATURE BIRTH, AND LOW BIRTH WEIGHT” is posted in a conspicuous place upon the premises. This subsection (b) does not apply to sales of cigarettes through cigarette vending machines to which subsection (a) applies.