Final answer:
The average heart rate is multiplied by the length of time to find the number of beats.
Step-by-step explanation:
The subject of this question is Biology and it is a question that would typically be asked in a High School level biology class.
In order to find the number of beats a person would have in a given time period, we need to multiply the average heart rate (in beats per minute) by the length of time (in minutes).
For example, to find the number of beats in 2.0 years, we would multiply the average heart rate (72.0 beats/min) by the length of time in minutes (2.0 years * 365 days/year * 24 hours/day * 60 min/hour).