Answer with Step-by-step explanation:
We are given that 
F=<0,-8>=0i-8j=-8j

The component of force is divided into two direction
1.Along the plane 
2.Perpendicular to the plane
1.The vector parallel to the plane will be=
By using 
Force along the plane will be=
Force along the plane will be = N
N
By using 
Therefore, force along the plane=
2.The vector perpendicular to the plane=
The force perpendicular to the plane=
The force perpendicular to the plane= N
N
Therefore, 
Sum of two component of force=
Sum of two component of force=
Hence,sum of two component of forces=Total force.