Two samples, each with n = 10 scores, are selected from the same population. The variance for the first sample is s2 = 40 and the variance for the second sample is s2 = 50. If the null hypothesis is true, then how much difference should be expected, on average, between the two sample means?
Choose one answer.
a. impossible to determine without additional information
b. 3 points
c. 90 points
d. 45 points