The demographic transition model

Some questions:
1) What is the Demographic Transition Model and what is this for?
2) Explain, according to the video why do the Death rate drop so rapidly in Stage
3) Explain in which stage the natural increase is greater and why.
4.-What 3 negative affects might a rapidly increasing population have on a country?
5.- Why is a rapidly decreasing population also a problem?
6.- The demographic transition model shows the interaction between which three variables?
7.- Give 2 possible reasons why the death rate drops rapidly in stage 2 of the demographic transition model
8.- Why is there a population boom during stage 2?
9.- At what point does a country enter stage 4 of the demographic transition model?
10.- What is a population pyramid?
11.- How does the population pyramid divide the country’s population?
12.- What does it show if the bottom of the population pyramid is wide?
13.- What does it show if the top of the population pyramid is thin?
14.- What two tools can we use to analyse a country’s population growth?