14.29 Determine the critical value that would be used to test the following hypotheses for experiments involving two independent samples, using the classical method:

a. Ho: Average(A)  Average(B)

Ha: Average(A)  Average(B)

with nA  18, nB  15, and   0.05.

b. Ho: The average score is the same for both groups.

Ha: Group I average scores are less than those for group II.

with nI  78, nII  45, and   0.05.