What is the approximate dose to the patient per "look" assuming each "look" lasts 12 seconds?

The correct response to the question regarding the approximate dose to the patient per "look," given that each look lasts 12 seconds, is based on typical dose calculations for fluoroscopy procedures.

In many clinical settings, the dose during fluoroscopy is measured in millirads or rads, depending on the duration of exposure and the equipment used. A dose of approximately 400 millirads corresponds with many standard fluoroscopic procedures for a brief examination period. This is a low dose, as is appropriate for short duration exposures, which do not substantially increase the risk to the patient.

Other choices presented, such as 5 rads and 400 rads, signify significantly higher radiation doses than what would typically be administered in a short examination setting. The dose of 5 millirads would be too low to represent the exposure associated with a standard 12-second look in fluoroscopy. Therefore, 400 millirads is a realistic approximation for the dose received by the patient during this brief examination interval. This choice reflects the understanding of typical fluoroscopic exposure and safety considerations in radiological practice.