Question: One sample has n = 4 scores with SS = 100 and the second sample has n = 8 scores with SS = 140.

(a) Calculate the pooled variance for the two samples

(b) Calculate the estimated standard error for the sample mean difference.

(c) If the sample mean difference is 6 points, is this enough to reject the null hypothesis for a two-tailed test with \(\alpha =0.05\) ?

(d) If the sample mean different is 9 is this enough to reject the null hypothesis for a two-tailed test with \(\alpha =0.05\) ?