To test: Whether there is sufficient evidence to reject the claim that wearing a helmet has no effect on whether facial injuries are received or not. To check: Whether a helmet seems to be effective in helping to prevent facial injuries in a crash or not.

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Chapter 11, Problem 4RE

To determine

To test: Whether there is sufficient evidence to reject the claim that wearing a helmet has no effect on whether facial injuries are received or not.

To check: Whether a helmet seems to be effective in helping to prevent facial injuries in a crash or not.

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