Experts from the Dean's Office decided to conduct a comparative study of final exam grades between two independently collected groups of students. Sample sizes were equal:n₁=n₂= 9.In addition, records from each group were assumed to be normal with KNOWN population standard deviations. Summaries and assumptions are presented in the table below.

Group	Size =n	Mean =X	Population SD =	2/n
HISTORY	n1= 9	(X)1= 65.8	1= 9	(1)2/n= 81/9 = 9
STAT	n2= 9	(X)2= 74.7	2= 12	(2)2/n= 144/9 = 16

At the significance level= 0.05,do you have sufficient evidence that the population average performance among History classes is BELOW that in STAT?

1. Specify the Critical Value

2. Evaluate the Test Statistic

3. State and IMPLEMENT the Rejection Rule