The prices of used books at a large college bookstore are normally distributed. If a sample of 23 used books from this store has a mean price of $27.50 with a standard deviation of $6.75, use Table 10.1 to calculate the following for a 95% confidence level about the population mean. a. Degrees of freedom b. The critical value of t c. The margin of error d. The confidence interval for a 95% confidence level

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