In a random sample of 23 cars brought in for repairs, the mean cost of repairs was $349.00, with a standard deviation of $38. Construct a 95% confidence interval for the population mean. Assume that auto repair costs are normally distributed.     $333.47 to $364.53 $333.47 to $364.53 $326.99 to $371.01 $326.99 to $371.01 $326.00 to $372.00 $326.00 to $372.00 $332.57 to $365.43

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