In electricity, the periodicity of electromagnetic waves is called _______

When visiting a home care patient receiving nasal O2 at 2 L/min through an O2 concentrator, you measure the FiO2 of the outlet gas as 0.63. Which of the following best explains this finding?

a. This FiO2 is normal at this flow. b. The sieve pellets are exhausted. c. The gas inlet filter must be clogged. d. Electrical power is inadequate.

An indented description or term indicates that:

A. it attaches to the description or term that appears at the margin of the column above. B. codes have been deleted. C. this is the complete description of this code. D. it is an add-on code.