A force F acting on an object varies with distance $x$ as shown here. The force is in N and $x$ in m. The work done by the force in moving the object from $x$ = 0 to $x$ = 6 m is
18.0 J
13.5 J
4.5 J
9.0 J
A force F acting on an object varies with distance $x$ as shown here. The force is in N and $x$ in m. The work done by the force in moving the object from $x$ = 0 to $x$ = 6 m is