An airplane travels 5508 kilometers against the wind in 9 hours and 6408 kilometers with the wind in the same amount of time. What is the rate of the plane in still air and what is the rate of the wind?​

Researchers were interested in whether relaxation training decreases the number of headaches a person experiences. they randomly assigned 20 participants to a control group or a relaxation training group and noted the change in number of headaches each group reported from the week before training to the week after training. which statistical analysis should be performed to answer the researchers' question?