Twenty students assigned to an experimental group receive 30 in a control group has a mean of 38 on the test (with an estimated population standard deviation of 3); the control group has a mean of 35 (with an estimated population standard deviation of 5). Using the .05 level, what should the experimenter conclude?
(a) use the steps of hypothesis testing
(b)sketch the distributors involved
(c)explain your answer to someone who is familar with the test for a single sample, but not independent means