How do we measure and record our heart rate

To check your pulse at your wrist, place two fingers between the bone and the tendon over your radial artery — which is located on the thumb side of your wrist. When you feel your pulse, count the number of beats in 15 seconds. Multiply this number by four to calculate your beats per minute.

Explanation:

a1 = unhealthy

a2= healthy

a3= healthy

the answer is life structure