The results of sampling independent populations:

Sample 1from population1

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 variance are known. Test H0: Population 1 mean -Population 2 mean 0 at = 0.05.HA: (population1 mean -population 2 mean)> 0. This is a one tailed test with upper reject region and positive critical value.