The director of manufacturing of baseballs is investigating vendors who supply them regularly to ML baseball. The director would like to estimate the diameter of the baseballs that are currently used in the toy line to determine if they still comply with league specifications. The principal manufacturing vendor has specified that the baseballs are supposed to have a population mean diameter of 7.30 inches and a standard deviation equal to .04 inches. A random sample of 25 selected from a shipment indicates a sample average of 7.31 inches. Set up a 95% confidence interval estimate of the true average diameter of baseballs in this shipment. Does the director need to choose another manufacturer? Does the population of baseballs need to have a diameter that is normally distributed here?