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A pitching machine is calibrated to deliver a fastball at a speed of 98 miles per hour. Every day, a technician samples the speed of twenty-five fastballs in order to determine if the machine needs adjustment. Today, the sample showed a mean speed of 99 miles per hour with a standard deviation of 1.75 miles per hour. Assume the population is normally distributed. At a 95% confidence level, what is the t-value in relation to the critical value? A. The critical value exceeds the t-value by 1.3 standard deviations. B. The t-value exceeds the critical value by 1.5 standard deviations. C. The t-value exceeds the critical value by 0.8 standard deviations. |