Please refer me some good books for the preparation of UPSC NDA 2 GAT EXAM OF 2020..
The best books for the preparation of NDA 2 are the NCERT for mathematics,history,geography,physics,biology as the NDA exam is conducted by government and the NCERT books are also given by government.
The exam is 12th level exam and for that if you study NCERT till class 12th,it will clear all your concepts and for practice you can by NDA question bank and previous year question papers are enough.
Hope this will help,please feel free to ask if you have any further queries.
As I had cleared NDA myself, I would suggest for General Ability Test, solve as many as previous year paper as you can. Go for Arihant publication which provides you good sample papers as well as previous year paper as well with solutions. Also for current affairs,start reading newspaper that helps alot