Problem 10. (15 points) Dynacel batteries last 13.27 hours in a standard flashlight, on average. Dynacel engineers have developed a new manufacturing process that they hope will increase the mean life of their batteries. They will test a random sample of the new batteries to determine if the new process has indeed increased the average life of the batteries. For the test, their hypotheses are: (Use mu for xbar for X, sigma for , as needed.) Ho: Ha The test is 40 batteries made by the new process are randomly selected and tested. To test at 1% significance, what is the critical t-score (3 decimal places)? tcrit =0 The 40 randomly selected new batteries had a mean life of 14.57 hours with a standard deviation of 3.5 hours. Calculate the test statistic for the sample (round to 3 decimal places). t What is the test conclusion? A. Reject the null hypothesis: The test provides evidence that the mean is greater than 13.27 hours. B. Accept the alternative hypothesis: The test shows that the mean is 14.57 hours. C. Reject the alternative hypothesis: The test provides sufficient evidence to show the mean is not greater than 13.27 hours. D. Don't reject the null hypothesis: The test does not provide sufficient evidence to prove the mean is greater than 13.27 hours. E. Accept the null hypothesis: The test shows that the mean is 13.27 hours.