100 students take a test in 2018. The average score was 75 and the standard deviation of the final exams scores was 5. The following year (2019), the professor changed her teaching style, and then taught the class to 90 students, gave the same exam, and found an average score of 80 and a standard deviation of 8. . Compute the 95% confidence interval for the final exam score in ECON 540 for 2018. Interpret the interval.

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