Given the following reasoning and answer, what was the question? Humans can survive without water for four days. Ice can be melted into water, which consists of hydrogen and oxygen, using a simple cigarette lighter. Humans can survive without food for 30 to 40 days on average. Humans need carbohydrates, proteins, and fats that are contained in foods. Water does not contain fat, carbohydrates or protein.
 The answer: yes

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
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The question Would a diet of ice eventually kill a person?