A hardware manufacturer produces bolts used to assemble various machines Assume that the diameter of bolts produced by this manufacturer has an unknown population mean ja and the standard deviation is 0.1 mm Suppose the average diameter of a simple random sample of 50 bolts is 5.11 mm The 99% confidence interval is O a. (5.04; 5.18) b. (5.08:5.14) Oc. (5.14: 5.08) Od. (5.079: 5.15)
