FINAL 108. 1. A random sample of 36 cars of same model has an average gas mileage of 35 miles/gallon with a sample standard deviation of 3 miles/ gallon. Find: (a) the standard error, (6) the error, (c) the 95x confidence interval for the sample mean. X Ros. 2. A cell telephone company has claimed the the batteries average more than 4-hour of use per charge. A sample of 49 batteries lasts an averge of 3.8 hours and the sample standard deviation deviation is 0.5 hours. Test the company's claim = 0.01 significant level by comparing the calcwaled 2- score to the critical 2- score (W. Identify the null and alternative hypothesises (6 ) Find the calculated E-score (") Find the critical ?-score for the = 0 01 significant level (d) Justify your support or reject the alternative hypothesis a (Host, internal)