The diagram given here is the standard $ECG$ of a normal person. The $P-$ wave represents the:

Which one of the following statements is correct regarding blood pressure?

$ECG$ depicts the depolarization and repolarization processes during the cardiac cycle. In the $ECG$ of a normal healthy individual,one of the following waves is not represented?

Arrange and select the following events in the correct sequence during the measurement of blood pressure by a sphygmomanometer.
$i.$ Pulsatile sound disappears.
$ii.$ Cuff is inflated to block the brachial artery by external pressure.
$iii.$ First pulsatile sound is heard indicating systolic pressure.
$iv.$ Pressure in the cuff is slowly lowered.
$v.$ Cuff is wrapped tightly around the upper arm.

What is represented by the $P$-wave in an $ECG$?

Which of the following is a repolarization wave?