why is it harder to breathe when climbing up a high mountain?
a. The air compresses the lungs.
b. The air has more moisture.
c. The air is thinner.
d. The air pressure increases.
1 answer
c. The air is thinner.
a. The air compresses the lungs.
b. The air has more moisture.
c. The air is thinner.
d. The air pressure increases.
1 answer