a manufacturer of piston rings for automobile engines frequently tests the width of the rings for quality control. last week, a random sample of 15 rings were measured, and the mean and standard deviation of the sample were used to construct a 95 percent confidence interval for the population mean width of the rings. when all other things remain the same, which of the following conditions would have resulted in a wider interval than the one constructed? i. a sample size of 20 with 95 percent confidence ii. a sample size of 15 with 99 percent confidence iii. a sample size of 12 with 95 percent confidence responses