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? the heart rate increases for 6 minutes, remains constant for 19 minutes, and then gradually increases for 5 minutes. the heart rate decreases for 6 minutes, remains constant for 19 minutes, and then gradually increases for 5 minutes. the heart rate increases for 6 minutes, remains constant for 19 minutes, and then gradually decreases for 5 minutes. the heart rate remains constant for 6 minutes, increases for 19 minutes, and then gradually decreases for 5 minutes.

Explanation:

Step1: Analyze the graph's trend in the first 6 minutes

Looking at the graph, from \(t = 0\) to \(t=6\) minutes, the heart - rate line is going up. So the heart rate is increasing in the first 6 minutes.

Step2: Analyze the graph's trend from 6 to 25 minutes

From \(t = 6\) to \(t=(6 + 19)=25\) minutes, the heart - rate line is horizontal. A horizontal line on a heart - rate vs time graph means the heart rate is constant.

Step3: Analyze the graph's trend from 25 to 30 minutes

From \(t = 25\) to \(t = 30\) minutes (\(30-25 = 5\) minutes), the heart - rate line is going down. So the heart rate is decreasing.

Answer:

The heart rate increases for 6 minutes, remains constant for 19 minutes, and then gradually decreases for 5 minutes.