How have polar bears adapted to the harsh climate ans conditions of their enviroment?

You are correct to use the term adaptation, as are the other answerers who mention Natural Selection. It is nothing whatever to do with evolution, which is the hypothesis that animals change into different kinds of animals over time. The original bear kind had the genetic information for lots of variability, including pale fur or dark fur, thick fur/thin fur etc. Different populations of bears now have different subsets of the genetic information in the original bear kind.

It is the same priciple that we see in lions and tigers. They are descended from the same big cat kind, and can interbreed. Yet they have diverged to become two different, more specialised species, each with less genetic diversity than their big cat ancestor.

It is unlikely that one could ever breed a lion with tiger-like stripes. More.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.