2 3 r4 5 6 7 8 9 10 11 12 13 Perform a one-sample z-test for a population mean using the P-value approach. Be sure to state the hypotheses and the significance level, to compute the value of the test statistic, to obtain the P-value, and to state your conclusion. In the past, the mean running time for a certain type of flashlight battery has been 7.6 hours. The manufacturer has introduced a change in the production method which he hopes has increased the mean running time. The mean running time for a random sample of 40 light bulbs was 7.8 hours. Do the data provide sufficient evidence to conclude that the mean running time of all light bulbs, u, has increased from the previous mean of 7.6 hours? Perform the appropriate hypothesis test using a significance level of 0.05. Assume that o = 0.5 hours. H