To prepare for a triathlon, amanda starts from position a and rides her bike along a straight road for 12 miles to reach position b. at b, she turns left and rides along another straight road for 15 miles to reach position c. at c, she turns left again and rides 20 miles along a straight road to return to a. in δabc, what are m∠a, m∠b, and m∠c, respectively?

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?