This is Norberto as Laura says, the maximum they can give you is 180 days, but it depends on the immigration officer who touches you, he can ask you what you come and give you what he considers, 15 days, a month, etc. Anyway all this info you have to check with the US Embassy in Buenos Aires. Greetings.
All ages, 180 days, you have to leave and enter again. The tourist life lasts 10 years.
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