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

What is the normal blood pressure in a healthy human?

If repeated checking of blood pressure of an individual shows systolic $140$ $mm$ $Hg$ and diastolic $90$ $mm$ $Hg$ or higher,it indicates hypertension.

How will you interpret an electrocardiogram $(ECG)$ in which the time taken in the $QRS$ complex is higher?

Given below are two statements.
Statement $I$ - Graphical recording of electrical variations detected at the surface of body during their propagation through the wall of heart is electrocardiograph.
Statement $II$ - The instrument used for the graphical recording of electrical variations detected at the surface of body during their propagation through wall of heart is electrocardiogram.
In the light of above statements,select the correct option given below:

What is blood pressure?