A group of 8 students were given the same standardized test twice to see whether retaking the test affected the score. The table gives the score differences for the 8 students. Use the paired​ t-interval procedure to determine a 90​% confidence interval for the difference between the mean scores on the first test and the second test​ (retake). ​ (Note: d=16.25 and sd=39.98​.)

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