If $n ( A ) = 40$ $n ( B ) = 21$

question 78

Short Answer

If $n ( A ) = 40$ , $n ( B ) = 21$ , and $n ( A \cap B ) = 3$ , find $n ( A \cup B )$ .
​ $n ( A \cup B ) =$ __________

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Definitions:

SA Node

The sinoatrial node, a group of cells in the right atrium of the heart that sets the pace of the heartbeat.

P-R Interval

A measurement in electrocardiography representing the time between the onset of the P wave and the start of the QRS complex, related to atrial depolarization and AV nodal delay.

Ventricular Muscle

The muscle tissue that makes up the walls of the ventricles in the heart, responsible for pumping blood throughout the body.

Third Heart Sound

A very low-frequency heart sound that can be an indication of various heart conditions, often associated with heart failure.