Correct Answer: C

Rationale: The Sinoatrial (SA) Node, often called the heart's natural pacemaker, is situated within the upper wall of the Right Atrium. It initiates the electrical impulses that regulate the heartbeat. Choices A, B, and D are incorrect because the SA node is not located in the Mitral Valve, Right Ventricle, or Left Atrium. It is specifically positioned in the Right Atrium to coordinate the heart's rhythm and timing.

Correct Answer: A

Rationale: The correct answer is A: PT/INR. Prothrombin times (PT/INR) are commonly used to monitor patients on Coumadin (warfarin) therapy, an anticoagulant that slows the blood's ability to clot. Monitoring PT/INR levels helps ensure the patient is receiving the appropriate dosage of Coumadin. Choice B, CBC (Complete Blood Count), is a general test that provides information on red blood cells, white blood cells, and platelets but is not specific to monitoring coagulation therapy. Choice C, PTT (Partial Thromboplastin Time), is another coagulation test but is not as commonly used for monitoring Coumadin therapy. Choice D, WBC (White Blood Cell count), is unrelated to monitoring coagulation therapy and is used to assess immune system function.

Correct Answer: C

Rationale: Restraints should be removed every 2 hours to prevent complications. Moving the joints through their full range of motion helps prevent muscle shortening and contractures. Massaging the area promotes circulation and reduces the risk of pressure injuries. Removing restraints less frequently could lead to complications like decreased circulation and skin breakdown. Options A, B, and D are incorrect because they do not align with the standard practice of removing restraints every 2 hours to ensure patient safety and well-being.

Correct Answer: A

Rationale: Asking about the weather initiates the social or introductory phase of the interview, allowing the nurse to establish rapport with the client at the beginning. This question can help assess the client's mental status and set a friendly tone. In the body phase, the client responds to the nurse's inquiries, while during the closing phase, either the nurse or the client concludes the interview. Therefore, the best time to ask about the weather forecast is during the introduction phase to facilitate a positive start to the interaction.

Correct Answer: A

Rationale: Specific gravity in urinalysis measures the concentration of solutes in urine compared to that of distilled water. This comparison helps in assessing the kidney's ability to concentrate urine properly. It is a valuable test even in dehydrated patients as it provides insights into renal function. Specific gravity can be measured using various methods, including a refractometer or reagent strips. Normal specific gravity readings of human urine typically range from 1.005 to 1.030. Choice A is correct as it accurately describes the purpose of specific gravity in urinalysis. Choices B and C are incorrect as specific gravity remains relevant in dehydrated patients and can be measured using different techniques, not solely a refractometer.