Three admission test preparation programs are being evaluated. Suppose the scores obtained by a sample of 20 people who used the programs provided the following data. Program 
A  B  C 
530 450 600
400 530 640
470 400 590
540 420 470
470 490 570
620 360 610
550 560

Use the Kruskal-Wallis test to determine whether there is a significant difference among the three test preparation programs. Use α = 0.05. State the null and alternative hypotheses.