26287
RATIONALE : Despite a national reduction in the prevalence of cigarette smoking , ~ 19 % of the adult US population persists in this behavior , with the highest prevalence among 18 - 25 - year - olds .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
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