For a Person at Rest, the Velocity V (In Liters $v = 0.85 \sin \left( \frac { \pi t } { 2 } \right)$

Short Answer

For a person at rest, the velocity v (in liters per second) of airflow during a respiratory cycle (the time from the beginning of one breath to the beginning of the next) is given by
​ $v = 0.85 \sin \left( \frac { \pi t } { 2 } \right)$ ,
​
where t is the time (in seconds).
(Inhalation occurs when v > 0 and exhalation occurs when v < 0.)
Select the graph of this velocity function.
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