Answer to Question 1
PA upright
Rationale: Air-fluid levels will be best demonstrated with upright positioning or horizontal beam use during decubitus positions. Supine imaging will not allow a fluid line to develop. Lateral chest imaging isn't the most ideal to isolate fluid in a single lung because of right and left lung superimposition.
Answer to Question 2
involuntary motion
Rationale: Involuntary motion is motion a patient cannot control, bowel peristalsis and heart motion are examples.