Unity3d Android Game Making

Unity3d Android Game Making

I want to start making a 2d android game in unity 3d. But i actually want
to know something about the unity3d upgrades.My Questions are:-
1.What upgrade do i require to make a android gamelike unity pro,android
pro,etc.
2.And do i require any 2d plugins(toolkits) to make a 2d game(i actually
dont want to use those).
3.Next is it possible to add 2d objects and any tutorials?
4.How to set a 2d camera? any tutorials.
5.And are upgrades of unity one time priced or yearly or monthly? 6.And
can i use physics in unity?
Thank you... Plz answer my questions....