AoA fellows ... hoping you are doing good

well a cousin of mine is going to take 2017 CSS ... He is F.Sc-pre med. with no Geology background. Can You please elaborate following queries about Geology :

1) Is it like Forestry OR Geography ???
2) What is its average score ??
3) Can anyone please name some relevant websites and pdf books for Geology
4) Can relying only on its Past papers one can clear it ??????
5) Does it contain mathematical portion??


Jazakallah