according to the department of public health, the average age of a new smoker is 13 years old. a researcher working for the tobacco industry wishes to test the claim that the average age is no longer 13 years old. he surveys a sample of 144 new smokers and finds they have an average age of 13.5 years with a standard deviation of 2.5 years. do the sample data support the researcher’s claim? test the relevant hypotheses at a significance level of ????????