(b) air pressure inside the lungs is less than the external air pressure.
(c) diaphragm contracts and the rib cage expands.
(d) air pressure inside the lungs is the same as the external air pressure.
9 sandwiches
8 sandwiches
7 sandwiches
*This May seem very easy but i desperatley suck at math :(* ...?
Answer: Human Overpopulation Choice D from USATestPrep
Explanation: