\f\f(a) Do the data support the claim that the mean etch rate is the same for both solutions? In reaching your conclusions, use a xed-level test with 0: = 0.05 and assume that both pepulation variances are equal. (b) Calculate a P-value for the test in part (a). '(c) Find a 95% CI on the di'erence in mean etch rates. ((1) Construct normal probability plots for the two saniples. Do these plots provide support for the assumptions of normality and equal variances? Write a practical interpre- tation for these plots