<prompt> What is the normal total delay of the cardiac impulse in the A-V node bundle?0.22 second0.18 second0.16 second0.13 second  <response>: The impulse from the S-A node travels rapidly through the internodal pathways and arrives at the A-V node at 0.03 second, at the A-V bundle at 0.12 second, and at the ventricular septum at 0.16 second. The total delay is thus 0.16 second 