for each of the following, assume the 2 samples are selected from populations with equal means and calculate how much difference should be expected, on average, between the 2 sample means.

a)each sample has n = 5 scores with s^2 = 38 for the first sample, and s^2 =42 for the second.

b)each sample has n =20 scores with s^2 = 38 for the first sample and s^2 = 42 for the second.