How Do You Rank Normal Force in This Physics Problem?

[madah12]

Homework Statement

http://img24.imageshack.us/img24/7550/12929005.png

Homework Equations

The Attempt at a Solution

I don't think the normal force depends on mass so I wouldn't know how to rank I mean the normal force on the middle bottom and left bottom is the same so how can I rank?( i mean the force from box to wall = -force from wall to box so why would it depend on the mass)

 

[Doc Al]

I mean the normal force on the middle bottom and left bottom is the same so how can I rank?

Follow the instructions. "To rank items as equivalent..."