The heart is important for transporting oxygen to the muscles when we exercise. How does the heart rate change when we go from s
itting on a chair to running up the stairs? A. The heart rate stops.
B. The heart rate gets slower.
C. The heart rate gets faster.
D. The heart rate stays the same.
Like you might have studied. Heated hair expands while colder air contracts. So, the sound isn't able to move as efficiently in cold air than it would in warmer air.
