The figures show six situations where the same block is about to start sliding on either a horizontal or and inclined surface in the direction of the applied force The surfaces are all made of the same material. In all cases except Case A$,$ a force acts on the block parallel to the surface as indicated by the arrow in the diagram. The magnitude of the force in each situation is the same.

Rank the magnitude of the frictional force on the block from greatest to least for these situations. Use and $=$ signs to indicate your ranking.