Answer to Question 1
thyroid gland
Rationale: The structures found in the mediastinum are: Esophagus, Trachea, Heart, Great Vessels, and Thymus Gland. However, it should be noted that the thymus gland is a temporary gland that primarily helps support the immune system with production of antibodies during childhood years.
Answer to Question 2
leakage radiation
Rationale: Leakage radiation escapes from the tube housing and is not directed through the tube window or collimators.