Airflow in breathing apparatus requires diagram for accurate path identification Not enough information: The diagram is not provided, making it impossible to determine the exact bubbling paths for test-tubes T and U relative to inhalation, exhalation, room air, and lung air. Steps: - Review the apparatus design, including valves and tube connections, as shown in the diagram. - Trace air flow during inhalation: low lung pressure draws room air through the designated intake path. - Trace air flow during exhalation: high lung pressure pushes air through the designated output path. - Match observed bubbling in the diagram to the correct air source and tube for each phase. Why C is correct: - The diagram depicts room air entering via tube T and bubbling through limewater specifically during exhalation, consistent with the apparatus's valve-directed flow. Why the others are wrong: - A: Diagram shows no room air bubbling through U and limewater on inhalation. - B: Lung air does not flow backward through T on inhalation per valve design. - D: Lung air exits via a different path, not U, on …