What would be the fastest possible HR if the absolute refractory period for the cardiac myocytes was 250 ms?

How do you find the time duration (in ms) for each region of the PQRST in ECG? The BPM is 83.

Define cardiac output and given numerical values compute the cardiac output

In a cardiac contractile cell what is the mechanism involved in the change in membrane potential? Depolarization: P wave Repolarization: QRS Complex, Hyperpolarization: T wave Pacemaker: K+ and Na+ flow, Depolarization: Pca rises Repolarization: Pk rises Depolarization: Pna increases, Peak: Na channels close, Plateau: Calcium channels close & Potassium channels open, Repolarization Potassium flows out & Calcium flows in Pacemaker: K+ and Na+ flow, Depolarization: Pca rises Repolarization: Pk rises, 4. If channels close Depolarization: Pna increases, Peak: Na channels close, Plateau: Calcium channels open & Potassium channels close, Repolarization Potassium flows out & Calcium flows out