A researcher wants to know if providing free coffee before a morning exam improves student performance. In a randomized experiment, 6060 students receive coffee and 6060 do not. The mean exam score for the coffee group is 7878, while the mean for the no-coffee group is 7575. Both groups have a sample standard deviation of 66. Test whether coffee improves exam scores at the α=0.01 \alpha = 0.01 significance level.

At the α=0.01\alpha = 0.01 significance level, there is sufficient evidence to conclude that providing coffee improves exam scores

At the α=0.01\alpha = 0.01 significance level, there is insufficient evidence to conclude that providing coffee improves exam scores

A researcher wants to know if providing free coffee before a morn...

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