What percentage of the air we breathe is made up of oxygen?

a. 78%
b. 12%
c. 16%
d. 21%

Answer: d. 21%

Health Professions

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The levels of past, family, and social history are

a. none, pertinent, extended, comprehensive. b. brief, extended. c. pertinent, extended d. pertinent, complete.

Health Professions

Right eye cataract, secondary to primary open angle glaucomatous flecks:

A) H26.222, H40.001. B) H26.221, H40.10X0. C) H26.221, H40.001. D) H40.10X0, H26.221.

Health Professions