a block of mass 5kg starts from rest at point a and is accelerated by a force of 5 n over a total distance from point a to c as shown. the distance measured from point a to b is exactly 10 meters and is frictionless. the distance from b to c is rough and its length is unknown. the block finally comes to rest at point c. if the coefficient of kinetic friction between the rough surface and the mass is 0.5, determine the total distance the mass slides (from a to c).