IM SO DUMB IM SORRY BUT EHATS THIS ONE PLEASE ALSO ITS DUE IN 30 MINS

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?

How many sides does a regular polygon have if each exterior angle measure is 45 degrees explain your answer, i really don't understand this.

Sara made $253 for 11 hours of work. at the same rate how much would he make for 7 hours of work?