Anational manufacturer of ball bearings is experimenting with two different processes for producing precision ball bearings. it is important that the diameters be as close as possible to an industry standard. the output from each process is sampled and the average error from the industry standard is measured in millimeters. the researcher is interested in determining whether there is evidence that process b yields higher average errors than process a. the population standard deviations are unknown but assumed equal. if we test the null hypothesis at the .05 level of significance, what is the decision? the results are presented next.