We know that work is the dot product of Force and Displacement.

$W=F·\stackrel{⏜}{d}=Fd{\cos }^{\theta }$

Here $W$ is the work done, $F$ is the force, $d$ is the displacement, and $\theta$ is the angle between $\mathrm{F}$ and $d$.

Given that$$\begin{gathered} \mathrm{W}=18; \\ \mathrm{F}=90Nm, \\ then d = 0.2\mathrm{cm} \end{gathered}$$;

Work done is given by

$W=F D \cos \theta$

$18=90\times 0.2\times \cos \theta$

$1 = \cos \theta$

$\cos 0° = \cos \theta$

$\theta =0°$

As a result, the force-displacement angle is: $0°$