Listed below are amounts of strontium-90 in mBq per gram of calcium. In a simple random sample of baby teeth obtained from Pennsylvania residents and New York residents born after 1979. Use 0.05 significance level to test the claim that the mean amount of strontium-90 from Pennsylvania residents is greater than the mean amount from New york.
Pennsylvania 155, 142, 149, 130, 151, 163, 151, 142, 156, 133, 138, 161
New york 133, 140, 142, 131, 134, 129, 128, 140, 140, 140, 137, 143
Assume that the two samples are independent simple random samples selected from normally distributed populations and do not assume that the population standard deviations are equal.
A. Test the given claim using theP value method or critical value method
B. Construct a confidence interval suitable for testing the given claim.