The following statistics are calculated by sampling from four normal populations whose variances are equal:

x1 = 149, n1 = 10; x2 = 154, n2 = 10; x3 = 143, n3 = 10;

x4 = 139, n4 = 10; MSE = 51.3

a. Use Fisher's LSD method to determine which population means differ at α = 0.01.

b. Use Tukey's HSD method to determine which population means differ at α = 0.01.

c. Do all population means differ? Explain.