Final answer:
To estimate the heart rate with the 1500 method, you would need an ECG trace. However, for a heart rate of 150 bpm, the time per beat is calculated by dividing 60 seconds by 150 beats, resulting in 0.4 seconds per beat.
Step-by-step explanation:
The 1500 method is a technique used to estimate heart rate by counting the number of beats in a certain amount of time. To estimate the heart rate using the 1500 method, you divide 1500 by the number of small boxes on an ECG between two R waves. Unfortunately, without an ECG trace or the number of boxes between R waves, we cannot apply the 1500 method to the options provided (A. 50 bpm, B. 75 bpm, C. 100 bpm, D. 125 bpm). However, if we're looking at a standard calculation for time per beat when the heart rate is 150 bpm, we can simply divide 60 seconds by the beats per minute.
For example, if your heart rate is 150 beats per minute during strenuous exercise, the time per beat is 60 seconds divided by 150 beats per minute, which equals 0.4 seconds per beat.