19. 12-smoke * dr.

In a survey concerning the smoking habits of consumers it was found that 50% smoke cigarette A, 45% smoke B, 40% smoke C, 25% smoke A and B, 10% smoke B and C, 16% smoke C and A, 8% smoke all the three brands. What percentage do not smoke ?

A person smokes other person's tobacco smoke is called_____

What is smoke ?

Tobacco smoke is rich is