A machine produces metal rods used in an automobile suspension system. A random sample of 15 rods is selected, and the diameter is measured. The resulting data (in millimeters) are as follows: 8.24,...

A machine produces metal rods used in an automobile suspension system. A random sample of 15 rods is selected, and the diameter is measured. The resulting data (in millimeters) are as follows: 8.24, 8.25, 8.20, 8.23, 8.24, 8.21, 8.26, 8.26, 8.20, 8.25, 8.23, 8.23, 8.19, 8.28, 8.24. A conclusion has to be made at 1% significance that the mean rod diameter is greater than 8.20. What is the value of t_calc? Please report your answer in 3 decimal places.