Answer:
The vascular system
Explanation:
The human blood circularitory system can be used to explain capillary action in the human body, our heart pumps blood in and out with no use of external forces.
 
        
             
        
        
        
Answer:
According to the image, the approximate QT interval is 0.4 seconds.
Explanation:
The QT interval is the space between the beginning of the QRS complex and the end of the T wave, which represents from the beginning of depolarization to ventricular repolarization.
Considering that the extandardized measurements of an EKG, where the paper circulates at a speed of 25 mm/s, 1 mm horizontal —measuring time— has an equivalence of 0.04 s.
In the image, there is 10 mm between the beginning of the QRS and the end of the T wave, so:
     0.04 seconds X 10 mm = 0.4 seconds.
Then, the estimated QT interval is 0.4 seconds.
 
        
             
        
        
        
Answer:
D)They ensure valid results.
Explanation: