A standardized test is given to a sixth grade class. Historically the mean score has been 143 with a variance of 26. The superintendent believes that the variance of performance may have recently increased. She randomly sampled 29 students and found a mean of 153 with a standard deviation of 7.9245. Is there evidence that the standard deviation has increased at the α=0.01 level?   State the hypotheses in terms of the standard deviation. Round the standard deviation to four decimal places when necessary.

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