Answer:
22.5 Nm
Step-by-step explanation:
The work done is the area under the force-displacement graph.
From A to P, the area is a rectangle.
From P to Q, the area is a trapezoid.
From Q to R, the area is a triangle.
From R to B, the area is a triangle.
The total area is:
(10 N) (1 m) + ½ (10 N + 15 N) (1 m) + ½ (15 N) (1 m) + ½ (-15 N) (1 m)
22.5 Nm