Question

the graph represents a persons heart rate in beats per minute during 30 minutes of exercise. which statement best describes the relationship between heart rate and time during exercise? cardiac exercise heart rate (bpm) the heart rate increases for 6 minutes, remains constant for 18 minutes, and then gradually decreases for 6 minutes. the heart rate increases for 6 minutes, remains constant for 18 minutes, and then gradually increases for 6 minutes.

Explanation:

Step1: Analyze graph segments

Observe the upward - sloping part (increase), flat part (constant), and downward - sloping part (decrease).

Step2: Determine time intervals

Count grid squares for time. Increase is 6 min, constant is 18 min, decrease is 6 min.

Answer:

The heart rate increases for 6 minutes, remains constant for 18 minutes, and then gradually decreases for 6 minutes.