In random samples of 25 from each of two normal populations,w e found the following statistics:
X/mean=524 S1=129
X/mean=469 S2=141
a. Estimate the difference between the two populations means with 95% confidence.
b. Repeat part a, increasing the standard deviations to S1=255 and S2=260.
c. Describe what happens when the sample standard deviations get larger.
d. Repeat part a with sample of size 100.
e. Discuss the effects of increasing the sample size.