How does the body create a difference between atmospheric and intrapulmonary pressures to cause air flow to and from the lungs

Which of the following is a cost of urbanization? a-cities can provide a high standard of living. b-cities are hubs of entertainment and education. c-paving over land changes the environment. d-job opportunities are greater in urban centers.

What are some things that limit population growth?

Number and variety of living organisms includes genetic, species, and ecological types