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A research team took a sample of 8 observations from the random variable Y, which had a normal distribution N(u, oz). They observed y: - 98.7, where yo was the average of the 8 sampled observations, and s = 253.1 was the observed value of the unbiased estimate of oz, based on the sample values. Find the 99% confidence interval for o2. This problem is worth 50 points