Answer to Question 1
ANS: A
In patients with chronic pulmonary hyperinflation (emphysema), the PMI may be difficult to lo-cate. Because of the increase in anteroposterior diameter and the changes in lung tissue, systolic vibrations are not well transmitted to the chest wall.
Answer to Question 2
ANS: D
The first heart sound (S1) is produced by closure of the mitral and tricuspid (atrioventricular AV) valves during contraction of the ventricles.