Answer:
it would be "How many children are affected by natural disasters every year?"
Explanation:
While the cousin would have experience with the other three and would therefor have answers, Unless she was a professional she would not know the answer to the third.
I would say that based on this excerpt and your knowledge of American history, the stock market crash made Americans lose confidence in business because B. people worked diligently to participate in the building of the American dream with the understanding they would profit.
However, when the stock market crash happened, they lost all faith and confidence.
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