Question: After calling 911 and beginning CPR compressions, which of these describes the correct posture for delivering effective compressions? Sitting with your arms at a 45-degree angle and your hands on the upper half of the patient's sternum Standing over the patient with your hands on the upper third of the sternum Position yourself over the patient with your hands covering the xiphoid process of the patient's sternum Position yourself over the patient with your arms at a 90-degree angle, hands placed on the lower half of the sternum between the breasts