H a : 1 2 , = 0.01, n 1 = 19, n 2 = 22

H_a: μ₁ ≠ μ₂, α = 0.01, n₁ = 19, n₂ = 22

Use Table 5 in Appendix B to find the critical value(s) for the alternative hypothesis, level of significance a, and sample sizes n₁ and n₂. Assume that the samples are random and independent, the populations are normally distributed, and that the population variances are

(a) Equal

(b) Not equal.