Four different blocks are resting on the floor. They each have a different mass, and they are each made of a different material, so the coefficients of friction are not the same. Using the information in the table below, rank, from highest to lowest, the magnitude of the maximum horizontal force, , which could act on each block before it begins to move.


Block Mass (kg) Coefficient
A 40 0.5
B 80 0.4
C 30 0.7
D 35 0.9