An object with a mass of 12kg slides down an inclined plane at a constant velocity. The plane is incline at an angle of 31 degrees. What is the coefficient of kinetic friction?

1. Find the force that gravity exerts on the object down the plane.
2. From this, can you state the force due to friction?
3. From that force, use where mu is the coefficient of friction and R is the normal reaction of the plane on the object.