A block of mass M 10 kg is placed on a rough horizontal plane characterized by a coefficient of friction. To the block they are connected, through ropes and pulleys all of negligible masses, two other blocks arranged vertically: on the left there is a block of mass M-5kg while on the on the right a block of mass M =15kg. Knowing that the M block moves to the right reaching the edge of the floor after having traveled a distance of s=1m and having reached the speed u-2m/s, determine the coefficient of friction with the surface.