What is the covering of the heart known as?

By counting the number of which of the following waves, the heartbeat of a person can be determined?

Which of these cells are thrombocytes formed from?

What is the average cardiac output for a healthy individual?

The heart is covered by a membranous bag of how many walls?

What is the minimum blood pressure for hypertension?

Which of these are not involved in the coagulation of blood?

What is the location of the SAN?