What are some of the reasons the birth rate
is very high in stage 1 countries?

birth Rate, Death Rate, Natural Increase and The Reasons for Changes in Birth and Death rate.)

Explanation:

radiative zone

explanation    

radiative zone is the layer of the sun which energy is transferred away from the core by radiation. although, the core is the only part of the sun that produces an appreciable amount of heat through fusion. in fact, 99% of the energy produced by the sun takes place within 24% of the sun's radius.