According to the historical data, the life expectancy in the United States is equal to the life expectancy in Germany. A new study has been made to see whether this has changed. Records of 225 individuals from the United States who died recently are selected at random. The 225 individuals lived an average of 77.7 years with a standard deviation of 4.5 years. Records of 255 individuals from Germany who died recently are selected at random and independently. The 225 individuals lived an average of 76.5 years with a standard deviation of 4.6 years. Assume that the population standard deviation of the life expectancy can be estimated by the sample standard deviations, since the samples that are used to compute them are quite large. At the 0.01 level of significance, is there enough evidence to support the claim that the life expectancy, mu 1 , in the United States is not equal to the life expectancy,mu 2 , in Germany anymore? Perform a two-tailed test. Then answer

a. The null hypothesis #

b. The alternative hypothesis #

c. The type of test statistic Choose only one, and degrees of freedom if necessary. z?, t?, chi square or F

d.The value of the test statistic (round to at least 3 decimal places)

e. The two critical values at the 0.01 level of significance. value 1? Value 2?(round to at least 3 decimal places)

f. can we support the claim that the life expectancy in the USA is not equal to the life expectancy in Germany. Yes or NO