Barium absorbs X-rays and appears on the fluorescent screen as
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Where is the X-ray grid placed?
At the output of the X-ray tube
B. Above the patient
C. Between the patient and the detector
What is the diaphragm used for positioning
A. Vision
B. Center point of the detection system
C. X-ray beam
D. A and C
What causes ionizing radiation to cause damage?
A. Break covalent bond, produce ionic salt, make electrolyte unbalance
B. Generates heat in the tissue
C. Destroy DNA
D. Heating water in cells causes overheating
4D ultrasound imaging is
A. a) faster than 3d ultrasound.
B. b) the addition of a time dimension to 3d ultrasound imaging.
C. c) used to visualize bony structures.
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