The correct answer is letter A
Sinoatrial node (SA) or pacemaker or sino-atrial node: special region of the heart, which controls the heart rate. It is located near the junction between the right atrium and the superior vena cava and consists of a cluster of specialized muscle cells. The rhythmic frequency of these muscle fibers is approximately 72 contractions per minute, while the atrial muscle contracts about 60 times per minute and the ventricular muscle, about 20 times per minute. Due to the fact that the sinoatrial node has a faster rhythmic frequency in relation to the other parts of the heart, the impulses originating from it spread to the atria and ventricles, stimulating these areas so quickly, so that the rhythm of the SA node becomes the rhythm of the whole heart; that's why it's called a pacemaker.
It tanked because all of the money was spent on the war. It became very inflated.
Alive and moving so the path could not be found
Answer:
Try making a checklist or schedule for the day, it motivates you to do more things in order to tick things of, it also keeps you organised and can help you prioritise certain things, but try to leave space for some relaxation of some sort. take notes in lectures as they may come in handy later and don't be scared to ask professors for help or to elaborate on the task that they have asked you to do
Answer:
Win varsity letters in four sports
Baseball, basketball, football, and track
Explanation:
