I believe your answer is B.Good Luck mate.
Answer:
Cardiac output
Explanation:
In the circulatory system, blood is pumped in and out of the heart to other body organs by veins and arteries.
The amount of blood that is pumped by the heart can be measured.
Cardiac output refers to the amount of blood that is pumped per minute by the heart.
It is an important measure because cardiac output indicates how efficient the heart meats the body demand
It is determined by the stroke volume and the heart rate.
<span>Humans add greatly to the carbon cycle by "</span>exhalation of carbon<span> dioxide, the burning of fossil fuels, deforestation and other poor agricultural practices."
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