At one point in the video, someone is balancing a chemical reaction. The person writes a coefficient of 2 in front of Fe2O3 but then writes a 4 for the number of iron (Fe) atoms. Explain this difference.

Blood pressure the total amount of blood the heart pumps in one minute 2. cardiac output the number of times your heart beats in a minute 3. dilate the amount of blood that the heart can pump in a single beat 4. heart rate the force exerted on the walls of the blood vessels by the blood that moves through them 5. stroke volume to widen or get larger in size