1. Multiple Choice: A patient with chronic obstructive pulmonary disease (COPD) is receiving oxygen therapy. Which of the following oxygen delivery systems would provide precise oxygen concentration? A. Nasal cannula B. Venturi mask C. Simple face mask D. Non-rebreather mask Answer: B. Venturi mask Rationale: The Venturi mask is able to deliver a precise oxygen concentration, which is crucial for COPD patients who may retain carbon dioxide if given too high a concentration of oxygen. 2. True/False: In adults with advanced heart failure, a biventricular pacemaker is often used to improve the ejection fraction. Answer: True Rationale: A biventricular pacemaker can resynchronize the heart's ventricles, potentially improving the ejection fraction and symptoms in patients with advanced heart failure.