Two blocks are connected by a rope and a pulley.  Neglect the masses of the rope and pulley.  Block 1 of mass 20 kg is on an inclined plane with a slope of 40°, the coefficient of friction between the block and the surface of the plane is 0.25.  While beam 2 is in a free hanging position.  If block A is sliding at a constant speed, what is the mass of block 2?