Answer
The work done is 1970 foot-pounds.
Work Step by Step
Here, the wagon is pulled horizontally such that the angle between the force and direction of motion is $38{}^\circ $.
Now, it is known that
$\mathbf{W}=\left\| \mathbf{F} \right\|\left\| \mathbf{AB} \right\|\cos \theta $ …… (1)
As it is given that
$\left\| \mathbf{F} \right\|=25,\left\| \mathbf{AB} \right\|=100$ and $\theta =38{}^\circ $ …… (2)
Therefore, use (2) in (1).
So,
$\begin{align}
& \mathbf{W}=\left( 25 \right)\left( 100 \right)\cos \left( 38{}^\circ \right) \\
& =\left( 2500 \right)\left( 0.788 \right) \\
& \approx 1970
\end{align}$
