400 J of Work Is Needed to Push an Object

4.00 J of work is needed to push an object of mass 2.00 kg from point A to point B of the inclined plane as shown in Figure 8-9. The angle of inclination is 30.0° with the horizontal. The height of the plane is h and the coefficient of friction between the object and the plane is 0.400. What is the length of the inclined plane? Use g = 10.0 m/s².

A) 0.319 m
B) 1.39 cm
C) 0.135 m
D) 0.236 m
E) 2.51 m