4. Guidelines for the Jolly Ellue Giant Health Insurance Company say that the average hospitalization for a triple hernia operation should net exceed 30 hours. A diligent auditor studied records of to randomly chosen triple hernia operations at Hackmore Hospital and found a mean hospital stay of 40 hours with a standard deviation of 20 hours. "Aha!\" she cried, \"the average stay exceeds the guideline." At o = .025, the critical value for a right-tailed test of her hypothesis is: a. 2.131 b. 1.9% c. 1.?53 .......... s'.'"""tiii"ilea"iiiall"iifaEiti'iiiia"Elatiii"'i'iiii"'ii"'5'iii'iii'"i55iiiiEiii"ail'i'i"'iti'ii5iii36H\""""""""""""" average in a certain type of portable CD player. But tests on a random sample of 18 batteries from a day's large production run showed a mean battery life of 3?.8 hours with a standard deviation of 5.4 hours. To test DullCo's hypothesis, the test statistic is: a. 2.11 b. AQEU c. 4.981] d. 4328 6. The process that produces Sonora Bars {a type of candy} is intended to produce bars with a mean weight of 5b gm. The process standard deviation is known to be 0?? gm. A random sample of 49 candy bars yields a mean weight of 55.82 gm. Which are the hypotheses to test whetherthe mean is smaller than it is supposed to be? a. HID: p :56: H1: pi b. HD1p :56: H1: p256 c. HID: p 255, H1: p s56 d. HID: p s55, H1: p #51