The function \( s(a) = 525,600a \) represents the total number of minutes in a person's life based on their age in years, since there are 525,600 minutes in a year (60 minutes/hour × 24 hours/day × 365 days/year).
To identify the correct interpretation of the function \( s(a) \):
- The first option: "the total number of heartbeats in a lifetime of a person who is a years old" is applicable, but needs clarification regarding how heart rates relate to the lifespan.
- The second option: "the heart rate of a person who is a minutes old" is incorrect as \( s(a) \) relates to years, not minutes.
- The third option: "the total number of heartbeats in a lifetime of a person who is a minutes old" is incorrect because the function is defined in terms of years.
- The fourth option: "the heart rate of a person who is a years old" refers to the function \( r(a) \), not \( s(a) \).
Thus, the correct response regarding the function \( s(a) = 525,600a \) is:
the total number of heartbeats in a lifetime of a person who is a years old.
Remember that to find the total heartbeats, you would need to multiply the heart rate (from \( r(a) \)) by the lifespan in minutes.