Use this information for Questions 7 - 8: Question 7: Calculate a confidence interval with a confidence level for true average lifetime. Sample mean is 1191.6 and 5 = 506.6 and n=43 (865.0, 1491.3) (901.2. 1705.7) (794.5. 1023.8) (992.3, 1390.9) Question 8 Use this information for Questions 7 - 8: Question 8: What is the z critical value for this problem? Sample mean is 1191.6 and s = 506.6 and n =43. ⢠2.58 196
