Question

what is cardiac output?
amount of blood heart pumps per unit of time
the amount of blood in the capilaries
the amount of blood in the body
the amount of blood in the veins
the amount of blood in the arteries

Explanation:

Cardiac output is defined as the amount of blood the heart pumps per unit of time. It is calculated by multiplying stroke volume (the amount of blood pumped per heartbeat) by heart rate (the number of heartbeats per minute). The other options refer to different aspects of blood volume or distribution (e.g., in capillaries, body, veins, arteries) rather than the heart's pumping action over time.

Answer:

Amount of blood heart pumps per unit of time