How many shades of gray can the unaided human eye detect?

a. 32
b. 320
c. 3,200
d. 32,000


a. The human eye can detect only about 32 shades of gray. Digital radiographic systems claim the ability to produce up to 65,500 gray levels, but monitors can only display 256 gray levels.

Health Professions

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Two simple repairs of the scalp are done; one laceration was 10 cm, and the other laceration was 5 cm. Report code(s) _____

a. 12005 b. 12002, 12004 c. 12001 d. 12034

Health Professions

Which of the following skill category distinctions is popular in textbooks related to methods of teaching motor skills?

A. Gross vs. fine motor skills B. Open vs. closed motor skills C. Stability vs. transport motor skills D. Discrete vs. continuous motor skills

Health Professions

General guidelines for safe ambulance driving include all of the following, EXCEPT:

A. avoiding one-way streets whenever possible. B. assuming that other drivers will not see you. C. regularly using the siren as much as possible. D. avoiding routes with heavy traffic congestion.

Health Professions

Proper placement of the King LT airway is performed by all of the following techniques, EXCEPT:

A) auscultation of bilateral breath sounds. B) the esophageal detector device. C) quantitative waveform capnography. D) observation for symmetrical chest rise.

Health Professions