Question

cardiac exercise
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.
the heart rate decreases for 6 minutes, remains constant for 18 minutes, and then gradually increases for 6 minutes.
the heart rate remains constant for 6 minutes, increases for 18 minutes, and then gradually decreases for 6 minutes.
quiz
mark and return
5 of 10
save & exit

Explanation:

1. Analyze the graph's first segment: Starts at (0, 75) and rises to (6, 135) → heart rate increases for 6 minutes.
2. Analyze the middle segment: Stays at 135 from (6, 135) to (24, 135) → constant for \(24 - 6 = 18\) minutes.
3. Analyze the final segment: Falls from (24, 135) to (30, ~105) → gradually decreases for \(30 - 24 = 6\) minutes.
4. Match this sequence to the given options.

Answer:

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