A high school principal asks a physical education teacher and a football coach to obtain a sample of 20 students each to compare times in physical activity each week. The physical education teacher randomly selects 20 students from her classes, and the football coach randomly selects 20 students from the football teams. Do you expect the comparison to be fair? Explain.

Which of the following would be a correct step in proving that triangle abc is congruent to triangle cda? a. use a protractor to measure the angles and show that all the corresponding angles are equal in measure. this will allow you to prove congruence by aaa. b. show that segment ab is parallel to segment cd and segment ad is parallel to segment cb. this will allow you to prove congruency by asa. c. show that is segment ab is perpendicular to segment ad. this will allow you to prove congruence by sas. d. none of the above.