What are the characteristics of stage 2 countries? examples?
what are the characteristics of stage 3 countries? examples?
what are the characteristics of stage 4 countries? examples?

I assume you are talking about the demographic transition model. Stage 2 countries have very high birth rates and somewhat falling death rates. Stage 2 country examples are Sub-Saharan Africa countries like Zimbabwe or Angola. Stage 3 is characterized by a population explosion (a large increase in population). The death rate falls, and the birth rate falls slightly (sign of industrialization). These countries are developing countries like Mexico or Indonesia. Stage 4 is where both the birth rate and death rates are low, such as more developed countries. Stage 4 countries are like the United States or China.

Water flows along the east coast and across the western tropical pacific towards south america, while they both are directed towards that way,  el niño does not directly affect the southern flow of water along the coast.