Answer:
he is making assumptions
Explanation:
Based on the information provided within the question you can gently point out to him that he is making assumptions. Your friend is basically providing a cause to a situation without having any evidence only the correlation between two variables that are otherwise not connected at all. There can be a vast list of reasons why U.S population has grown and with more population means there needs to be more cars being produced. Yet there are no facts indicating that a reduction in auto production will cause a reduction in US population.
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