1 The mean voltage and standard deviation of 12 batteries from each manufacturer were 2 measured. The results are summarized in the following table. 3 Manufacturer Sample mean Population standard voltage (millivolts) deviation(millivolts) A 167 5 B 163 4 What type of hypothesis test should be performed? Select What is the test statistic? Ex: 0.123 What is the number of degrees of freedom? Ex: 25 Does sufficient evidence exist to support the claim that the voltage of the batteries made by the two manufacturers is different at the a = 0.01 significance level? Select v