i) Five samples of a substance were used to determine if there is a difference between a laboratory chemical analysis and an X-ray fluorescence analysis of the iron content.Each sample was split into two subsamples, one subsample applied the chemical analysis, and one subsample applied the X-ray fluorescence analysis.The iron content data that applied the chemical analysis isx1= {2.2, 1.9, 2.5, 2.3, 2.4}. The iron content data that applied the X-ray fluorescence analysis isx2= {2.0, 2.0, 2.3, 2.1, 2.4}.Assuming that the populations are normal, suppose we want to test whether the two methods of analysis give the same result on average, what test would we conduct?

a) Independent two samplet-test for difference of means

b) None of the other choices is correct.

c) Matched pairst-test for mean of difference

d) Independent two samplez-test for difference of proportions

ii) If we want to obtain the test statistic, what would be the value in the numerator?