Population growth

Week 2 – Discuss Human Population Growth, Affluence, and the Environment Population growth is critical to environmental change. The IPAT equation (from both Week 1 and 2 readings) is an equation that describes four variables that interact to produce environmental change:
I = P x A x T
where I reflects the environmental impact, P the population size, A the level of affluence/consumption per person, and T the impact of technology use.
This week, we are learning about past, current, and projected future population growth and the underlying factors and causes. We also explore some different population growth scenarios in the Week 2 – Eco Moment (Population Growth Calculator).  
Based on your understanding of these issues, please answer the following questions:

Given this equation, what drives environmental decline?
Compare the United States with a developing country of your choice and conduct some research. How do the factors given in the I=PAT equation differ for these two countries? Can you calculate or find actual calculations of the value I?
Describe one or two of the most pressing environmental issues faced by the developing country you selected. How are these issues related to population growth and affluence in this country? Consider age structure, population growth rate, and standard of living here.
Please select a developing country not yet discussed by a classmate for your main response and include the name of the country in the header for your post. When responding to your classmates, please add to the discussion with a fact-supported addition, opinion, gentle correction, or example, citing reliable sources.