Read each situation and perform the appropriate test of hypothesis for the one sample mean z-test and t-test. 2. A manufacturer claims that their car batteries have a mean life expectancy of 6 years...

Extracted text: Read each situation and perform the appropriate test of hypothesis for the one sample mean z-test and t-test. 2. A manufacturer claims that their car batteries have a mean life expectancy of 6 years with a population standard deviation of 1.75 years. In order to test its own claim, a random sample of 35 batteries were tested and it was found out their mean life span is 5. 5 years. Is there evidence at the 0.01 level of significance that the batteries become exhausted in less than 6 years?