Final answer:
To answer the student's question, we calculate the total number of heartbeats in 2 years by multiplying the average heart rate (72.0 beats/min) by the total number of minutes in 2 years (1,051,200 minutes), which yields 75,686,400 beats. We then round the answer to the appropriate number of significant figures; hence the answer is (a) 7.6×107 beats, (b) 7.57×107 beats and (c) 7.57×107 beats.
Step-by-step explanation:
To calculate the number of heartbeats a person would have in a given time frame, we can use the following formula:
Number of beats = Average heart rate (beats/min) × Number of minutes.
First, we need to convert years into minutes. Since there are 525,600 minutes in a year (60 minutes/hour × 24 hours/day × 365 days/year), for 2 years we have:
2.0 years × 525,600 minutes/year = 1,051,200 minutes.
Now, we multiply the number of minutes by the average heart rate:
Number of beats in 2.0 years = 72.0 beats/min × 1,051,200 minutes = 75,686,400 beats.
The results should be reported with the appropriate number of significant figures. As the given heart rate has three significant figures, and the time of 2.0 years implies two significant figures, our final answer should be rounded to two significant figures.
Therefore, the answer is:
(a) 7.6×107 beats (b) 7.57×107 beats (c) 7.57×107 beats.