A skier of mass 63kg starts from rest and slid down an icy frictionless slope that has a length of 46 m at an angle of 37 degrees with respect to the horizontal. At the bottom of the slope, the path levels out and becomes horizontal, the snow becomes less icy and the skier begins to slow down, coming to rest at a distance of 113 m along the horizontal path. Calculate:

a) The speed of the skier at the bottom of the slope ,and 

b) The coefficient of the kinetic friction between the skier and the horizontal surface.