The results of sampling independent populations:

sample 1 from population 1

mean 80

population variance 3

sample size 25

sample 2 from population 2

mean 81

population variance 2

sample size 50

Note that the population variances are known. Test H0: (population1 mean - population2 mean) 0 at a = 0.05. HA: (population1 mean - population2 mean) > 0. This is a one-tailed test with upper reject region and positive critical value.