Chapter 12: Vectors and the Geometry of Space - Section 12.3 - The Dot Product - Exercises 12.3 - Page 713: 43

$\approx 3464.1\ J$

The work done by a constant force ${\bf F}$ acting through a displacement ${\bf D}=\vec{PQ}$ is ${\bf W}={\bf F}\cdot{\bf D}$ --- ${\bf F}\cdot{\bf D}=|{\bf F}|\cdot|{\bf D}|\cos\alpha$ ${\bf W}=(200\ N)(20\ m)(\cos 30^{\circ})$ $=4000\displaystyle \cdot\frac{\sqrt{3}}{2}\ Nm$ $=2000\sqrt{3}\ J$ $\approx 3464.1\ J$