A company manufactures ball bearings for precision machines. The average diameter of a certain type of ball bearing should be 6.0 mm. To check that the average diameter is correct, the company formulates a statistical test. a. What is the sampling distribution of the mean score x of a sample of 50 ball bearings given the standard deviation is 0.7 mm. b. State the null and alternative hypothesis. c. Suppose that one sample data gives x