a. Exercise 2 includes a confidence interval. If you use the P-value method or the critical value method from Part 1 of this section to test the claim that women and men have the same mean hemoglobin levels, will the hypothesis tests and the confidence interval result in the same conclusion?
b. In general, if you conduct a hypothesis test using the methods of Part 1 of this section, will the P-value method, the critical value method, and the confidence interval method result in the same conclusion?
c. Assume that you want to use a 0.01 significance level to test the claim that the mean hemoglobin level in women is less than the mean hemoglobin level in men. What confidence level should be used if you want to test that claim using a confidence interval?

Data From Exercise 2

Large samples of women and men are obtained,  and the hemoglobin level is measured in each subject. Here is the 95% confidence  interval for the difference between the two population means, where the measures from  women correspond to population 1 and the measures from men correspond to population 2: –1.76 g / dL < μ₁ – μ₂ < –1.62 g/dL.