The CPT code that should be reported by the obsterician is 76816.
CPT codes used for obstetrician ultrasound ranges from 76801 to 76821. The description of the codes is based on the procedures that are carried out.
CPT code 76816 is used to bill a follow up study. The medical examination perform in this case include: re-assessing the size and the interval growth of the fetus and examination of abnormality previously observed on previous scan. <span />
        
             
        
        
        
Answer: 
The particles that cause the aurora are energized in the magnetosphere, that is, above the atmosphere. If they don't reach 10,000 volts, they will still cause auroral light. The lower energy won't change the wave length of the light, but will cause the light to be dimmer.
Explanation: