A selection process to be set in a position in GM company. Candidates are requested to complete an aptitude test. The results from the test are assumed to follow a normal distribution with standard...

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Extracted text: A selection process to be set in a position in GM company. Candidates are requested to complete an aptitude test. The results from the test are assumed to follow a normal distribution with standard deviation, equal to 1.3. A simple random sample of 16 results from the test has a sample mean of 4.2. You are given a confidence interval computed by a researcher for the preceding data, going from 3.83 to 4.57. Which confidence level was used to compute this interval?