Independent random samples from normal populations produced the results shown in the next table.

Sample 1 Sample 2
1.2............................. 4.2
3.1............................. 2.7
1.7............................. 3.6
2.8............................. 3.9
3.0.............................
a. Calculate the pooled estimate of σ2.
b. Do the data provide sufficient evidence to indicate that µ2 > µ1? Test using α = .10.
c. Find a 90% confidence interval for (µ1 - µ2).
d. Which of the two inferential procedures, the test of hypothesis in part b or the confidence interval in part c, provides more information about (µ1 - µ2)?

Sample 1 Sample 2 1.2 3.1 1.7 2.8 3.0 4.2 2.7 3.6 3.9