For each of the following, calculate the pooled variance and the estimated standard error for the sample mean difference

A. The first sample has n=4 scores and a variance of s^2=17 and the second sample has n=8 scores and a variance of s^2=27.

B. Now the sample variances are increased so that the first sample has n=4 scores and a variance of s^2=68 and the second sample has n=8 scores and a variance of s^2=108

C. Comparing your answers for parts a and b, how does increased variance influence the size of the estimated standard error ?